Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II

The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan...
Ausführliche Beschreibung

Gespeichert in:

Autor*in:	Alexander P. Ji [verfasserIn] Joshua D. Simon [verfasserIn] Ian U. Roederer [verfasserIn] Ekaterina Magg [verfasserIn] Anna Frebel [verfasserIn] Christian I. Johnson [verfasserIn] Ralf S. Klessen [verfasserIn] Mattis Magg [verfasserIn] Gabriele Cescutti [verfasserIn] Mario Mateo [verfasserIn] Maria Bergemann [verfasserIn] John I. Bailey III [verfasserIn]

Format:	E-Artikel
Sprache:	Englisch

Erschienen:	2023

Schlagwörter:	Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution

Übergeordnetes Werk:	In: The Astronomical Journal - IOP Publishing, 2022, 165(2023), 3, p 100
Übergeordnetes Werk:	volume:165 ; year:2023 ; number:3, p 100

Links:	Link aufrufen Link aufrufen Link aufrufen Journal toc

DOI / URN:	10.3847/1538-3881/acad84

Katalog-ID:	DOAJ089162536

Internformat


LEADER	01000naa a22002652 4500
001	DOAJ089162536
003	DE-627
005	20230505015857.0
007	cr uuu---uuuuu
008	230505s2023 xx \|\|\|\|\|o 00\| \|\|eng c
024	7		\|a 10.3847/1538-3881/acad84 \|2 doi
035			\|a (DE-627)DOAJ089162536
035			\|a (DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709
040			\|a DE-627 \|b ger \|c DE-627 \|e rakwb
041			\|a eng
050		0	\|a QB1-991
100	0		\|a Alexander P. Ji \|e verfasserin \|4 aut
245	1	0	\|a Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II
264		1	\|c 2023
336			\|a Text \|b txt \|2 rdacontent
337			\|a Computermedien \|b c \|2 rdamedia
338			\|a Online-Ressource \|b cr \|2 rdacarrier
520			\|a The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization.
650		4	\|a Dwarf galaxies
650		4	\|a Local Group
650		4	\|a R-process
650		4	\|a Chemical abundances
650		4	\|a Galaxy chemical evolution
653		0	\|a Astronomy
700	0		\|a Joshua D. Simon \|e verfasserin \|4 aut
700	0		\|a Ian U. Roederer \|e verfasserin \|4 aut
700	0		\|a Ekaterina Magg \|e verfasserin \|4 aut
700	0		\|a Anna Frebel \|e verfasserin \|4 aut
700	0		\|a Christian I. Johnson \|e verfasserin \|4 aut
700	0		\|a Ralf S. Klessen \|e verfasserin \|4 aut
700	0		\|a Mattis Magg \|e verfasserin \|4 aut
700	0		\|a Gabriele Cescutti \|e verfasserin \|4 aut
700	0		\|a Mario Mateo \|e verfasserin \|4 aut
700	0		\|a Maria Bergemann \|e verfasserin \|4 aut
700	0		\|a John I. Bailey III \|e verfasserin \|4 aut
773	0	8	\|i In \|t The Astronomical Journal \|d IOP Publishing, 2022 \|g 165(2023), 3, p 100 \|w (DE-627)312175647 \|w (DE-600)2003104-X \|x 15383881 \|7 nnns
773	1	8	\|g volume:165 \|g year:2023 \|g number:3, p 100
856	4	0	\|u https://doi.org/10.3847/1538-3881/acad84 \|z kostenfrei
856	4	0	\|u https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709 \|z kostenfrei
856	4	0	\|u https://doi.org/10.3847/1538-3881/acad84 \|z kostenfrei
856	4	2	\|u https://doaj.org/toc/1538-3881 \|y Journal toc \|z kostenfrei
912			\|a GBV_USEFLAG_A
912			\|a SYSFLAG_A
912			\|a GBV_DOAJ
912			\|a GBV_ILN_11
912			\|a GBV_ILN_20
912			\|a GBV_ILN_22
912			\|a GBV_ILN_23
912			\|a GBV_ILN_24
912			\|a GBV_ILN_31
912			\|a GBV_ILN_39
912			\|a GBV_ILN_40
912			\|a GBV_ILN_60
912			\|a GBV_ILN_62
912			\|a GBV_ILN_63
912			\|a GBV_ILN_65
912			\|a GBV_ILN_69
912			\|a GBV_ILN_70
912			\|a GBV_ILN_73
912			\|a GBV_ILN_95
912			\|a GBV_ILN_105
912			\|a GBV_ILN_110
912			\|a GBV_ILN_151
912			\|a GBV_ILN_161
912			\|a GBV_ILN_170
912			\|a GBV_ILN_213
912			\|a GBV_ILN_230
912			\|a GBV_ILN_285
912			\|a GBV_ILN_293
912			\|a GBV_ILN_370
912			\|a GBV_ILN_602
912			\|a GBV_ILN_2006
912			\|a GBV_ILN_2014
912			\|a GBV_ILN_2088
912			\|a GBV_ILN_2110
912			\|a GBV_ILN_2129
912			\|a GBV_ILN_2522
912			\|a GBV_ILN_4012
912			\|a GBV_ILN_4037
912			\|a GBV_ILN_4112
912			\|a GBV_ILN_4125
912			\|a GBV_ILN_4126
912			\|a GBV_ILN_4249
912			\|a GBV_ILN_4305
912			\|a GBV_ILN_4306
912			\|a GBV_ILN_4307
912			\|a GBV_ILN_4313
912			\|a GBV_ILN_4322
912			\|a GBV_ILN_4323
912			\|a GBV_ILN_4324
912			\|a GBV_ILN_4325
912			\|a GBV_ILN_4335
912			\|a GBV_ILN_4338
912			\|a GBV_ILN_4367
912			\|a GBV_ILN_4700
951			\|a AR
952			\|d 165 \|j 2023 \|e 3, p 100

Indexfelder

author_variant	a p j apj j d s jds i u r iur e m em a f af c i j cij r s k rsk m m mm g c gc m m mm m b mb j i b i jibi
matchkey_str	article:15383881:2023----::eamxnitepoesnacdlrfitwrg
hierarchy_sort_str	2023
callnumber-subject-code	QB
publishDate	2023
allfields	10.3847/1538-3881/acad84 doi (DE-627)DOAJ089162536 (DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709 DE-627 ger DE-627 rakwb eng QB1-991 Alexander P. Ji verfasserin aut Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II 2023 Text txt rdacontent Computermedien c rdamedia Online-Ressource cr rdacarrier The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization. Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution Astronomy Joshua D. Simon verfasserin aut Ian U. Roederer verfasserin aut Ekaterina Magg verfasserin aut Anna Frebel verfasserin aut Christian I. Johnson verfasserin aut Ralf S. Klessen verfasserin aut Mattis Magg verfasserin aut Gabriele Cescutti verfasserin aut Mario Mateo verfasserin aut Maria Bergemann verfasserin aut John I. Bailey III verfasserin aut In The Astronomical Journal IOP Publishing, 2022 165(2023), 3, p 100 (DE-627)312175647 (DE-600)2003104-X 15383881 nnns volume:165 year:2023 number:3, p 100 https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709 kostenfrei https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/toc/1538-3881 Journal toc kostenfrei GBV_USEFLAG_A SYSFLAG_A GBV_DOAJ GBV_ILN_11 GBV_ILN_20 GBV_ILN_22 GBV_ILN_23 GBV_ILN_24 GBV_ILN_31 GBV_ILN_39 GBV_ILN_40 GBV_ILN_60 GBV_ILN_62 GBV_ILN_63 GBV_ILN_65 GBV_ILN_69 GBV_ILN_70 GBV_ILN_73 GBV_ILN_95 GBV_ILN_105 GBV_ILN_110 GBV_ILN_151 GBV_ILN_161 GBV_ILN_170 GBV_ILN_213 GBV_ILN_230 GBV_ILN_285 GBV_ILN_293 GBV_ILN_370 GBV_ILN_602 GBV_ILN_2006 GBV_ILN_2014 GBV_ILN_2088 GBV_ILN_2110 GBV_ILN_2129 GBV_ILN_2522 GBV_ILN_4012 GBV_ILN_4037 GBV_ILN_4112 GBV_ILN_4125 GBV_ILN_4126 GBV_ILN_4249 GBV_ILN_4305 GBV_ILN_4306 GBV_ILN_4307 GBV_ILN_4313 GBV_ILN_4322 GBV_ILN_4323 GBV_ILN_4324 GBV_ILN_4325 GBV_ILN_4335 GBV_ILN_4338 GBV_ILN_4367 GBV_ILN_4700 AR 165 2023 3, p 100
spelling	10.3847/1538-3881/acad84 doi (DE-627)DOAJ089162536 (DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709 DE-627 ger DE-627 rakwb eng QB1-991 Alexander P. Ji verfasserin aut Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II 2023 Text txt rdacontent Computermedien c rdamedia Online-Ressource cr rdacarrier The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization. Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution Astronomy Joshua D. Simon verfasserin aut Ian U. Roederer verfasserin aut Ekaterina Magg verfasserin aut Anna Frebel verfasserin aut Christian I. Johnson verfasserin aut Ralf S. Klessen verfasserin aut Mattis Magg verfasserin aut Gabriele Cescutti verfasserin aut Mario Mateo verfasserin aut Maria Bergemann verfasserin aut John I. Bailey III verfasserin aut In The Astronomical Journal IOP Publishing, 2022 165(2023), 3, p 100 (DE-627)312175647 (DE-600)2003104-X 15383881 nnns volume:165 year:2023 number:3, p 100 https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709 kostenfrei https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/toc/1538-3881 Journal toc kostenfrei GBV_USEFLAG_A SYSFLAG_A GBV_DOAJ GBV_ILN_11 GBV_ILN_20 GBV_ILN_22 GBV_ILN_23 GBV_ILN_24 GBV_ILN_31 GBV_ILN_39 GBV_ILN_40 GBV_ILN_60 GBV_ILN_62 GBV_ILN_63 GBV_ILN_65 GBV_ILN_69 GBV_ILN_70 GBV_ILN_73 GBV_ILN_95 GBV_ILN_105 GBV_ILN_110 GBV_ILN_151 GBV_ILN_161 GBV_ILN_170 GBV_ILN_213 GBV_ILN_230 GBV_ILN_285 GBV_ILN_293 GBV_ILN_370 GBV_ILN_602 GBV_ILN_2006 GBV_ILN_2014 GBV_ILN_2088 GBV_ILN_2110 GBV_ILN_2129 GBV_ILN_2522 GBV_ILN_4012 GBV_ILN_4037 GBV_ILN_4112 GBV_ILN_4125 GBV_ILN_4126 GBV_ILN_4249 GBV_ILN_4305 GBV_ILN_4306 GBV_ILN_4307 GBV_ILN_4313 GBV_ILN_4322 GBV_ILN_4323 GBV_ILN_4324 GBV_ILN_4325 GBV_ILN_4335 GBV_ILN_4338 GBV_ILN_4367 GBV_ILN_4700 AR 165 2023 3, p 100
allfields_unstemmed	10.3847/1538-3881/acad84 doi (DE-627)DOAJ089162536 (DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709 DE-627 ger DE-627 rakwb eng QB1-991 Alexander P. Ji verfasserin aut Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II 2023 Text txt rdacontent Computermedien c rdamedia Online-Ressource cr rdacarrier The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization. Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution Astronomy Joshua D. Simon verfasserin aut Ian U. Roederer verfasserin aut Ekaterina Magg verfasserin aut Anna Frebel verfasserin aut Christian I. Johnson verfasserin aut Ralf S. Klessen verfasserin aut Mattis Magg verfasserin aut Gabriele Cescutti verfasserin aut Mario Mateo verfasserin aut Maria Bergemann verfasserin aut John I. Bailey III verfasserin aut In The Astronomical Journal IOP Publishing, 2022 165(2023), 3, p 100 (DE-627)312175647 (DE-600)2003104-X 15383881 nnns volume:165 year:2023 number:3, p 100 https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709 kostenfrei https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/toc/1538-3881 Journal toc kostenfrei GBV_USEFLAG_A SYSFLAG_A GBV_DOAJ GBV_ILN_11 GBV_ILN_20 GBV_ILN_22 GBV_ILN_23 GBV_ILN_24 GBV_ILN_31 GBV_ILN_39 GBV_ILN_40 GBV_ILN_60 GBV_ILN_62 GBV_ILN_63 GBV_ILN_65 GBV_ILN_69 GBV_ILN_70 GBV_ILN_73 GBV_ILN_95 GBV_ILN_105 GBV_ILN_110 GBV_ILN_151 GBV_ILN_161 GBV_ILN_170 GBV_ILN_213 GBV_ILN_230 GBV_ILN_285 GBV_ILN_293 GBV_ILN_370 GBV_ILN_602 GBV_ILN_2006 GBV_ILN_2014 GBV_ILN_2088 GBV_ILN_2110 GBV_ILN_2129 GBV_ILN_2522 GBV_ILN_4012 GBV_ILN_4037 GBV_ILN_4112 GBV_ILN_4125 GBV_ILN_4126 GBV_ILN_4249 GBV_ILN_4305 GBV_ILN_4306 GBV_ILN_4307 GBV_ILN_4313 GBV_ILN_4322 GBV_ILN_4323 GBV_ILN_4324 GBV_ILN_4325 GBV_ILN_4335 GBV_ILN_4338 GBV_ILN_4367 GBV_ILN_4700 AR 165 2023 3, p 100
allfieldsGer	10.3847/1538-3881/acad84 doi (DE-627)DOAJ089162536 (DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709 DE-627 ger DE-627 rakwb eng QB1-991 Alexander P. Ji verfasserin aut Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II 2023 Text txt rdacontent Computermedien c rdamedia Online-Ressource cr rdacarrier The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization. Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution Astronomy Joshua D. Simon verfasserin aut Ian U. Roederer verfasserin aut Ekaterina Magg verfasserin aut Anna Frebel verfasserin aut Christian I. Johnson verfasserin aut Ralf S. Klessen verfasserin aut Mattis Magg verfasserin aut Gabriele Cescutti verfasserin aut Mario Mateo verfasserin aut Maria Bergemann verfasserin aut John I. Bailey III verfasserin aut In The Astronomical Journal IOP Publishing, 2022 165(2023), 3, p 100 (DE-627)312175647 (DE-600)2003104-X 15383881 nnns volume:165 year:2023 number:3, p 100 https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709 kostenfrei https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/toc/1538-3881 Journal toc kostenfrei GBV_USEFLAG_A SYSFLAG_A GBV_DOAJ GBV_ILN_11 GBV_ILN_20 GBV_ILN_22 GBV_ILN_23 GBV_ILN_24 GBV_ILN_31 GBV_ILN_39 GBV_ILN_40 GBV_ILN_60 GBV_ILN_62 GBV_ILN_63 GBV_ILN_65 GBV_ILN_69 GBV_ILN_70 GBV_ILN_73 GBV_ILN_95 GBV_ILN_105 GBV_ILN_110 GBV_ILN_151 GBV_ILN_161 GBV_ILN_170 GBV_ILN_213 GBV_ILN_230 GBV_ILN_285 GBV_ILN_293 GBV_ILN_370 GBV_ILN_602 GBV_ILN_2006 GBV_ILN_2014 GBV_ILN_2088 GBV_ILN_2110 GBV_ILN_2129 GBV_ILN_2522 GBV_ILN_4012 GBV_ILN_4037 GBV_ILN_4112 GBV_ILN_4125 GBV_ILN_4126 GBV_ILN_4249 GBV_ILN_4305 GBV_ILN_4306 GBV_ILN_4307 GBV_ILN_4313 GBV_ILN_4322 GBV_ILN_4323 GBV_ILN_4324 GBV_ILN_4325 GBV_ILN_4335 GBV_ILN_4338 GBV_ILN_4367 GBV_ILN_4700 AR 165 2023 3, p 100
allfieldsSound	10.3847/1538-3881/acad84 doi (DE-627)DOAJ089162536 (DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709 DE-627 ger DE-627 rakwb eng QB1-991 Alexander P. Ji verfasserin aut Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II 2023 Text txt rdacontent Computermedien c rdamedia Online-Ressource cr rdacarrier The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization. Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution Astronomy Joshua D. Simon verfasserin aut Ian U. Roederer verfasserin aut Ekaterina Magg verfasserin aut Anna Frebel verfasserin aut Christian I. Johnson verfasserin aut Ralf S. Klessen verfasserin aut Mattis Magg verfasserin aut Gabriele Cescutti verfasserin aut Mario Mateo verfasserin aut Maria Bergemann verfasserin aut John I. Bailey III verfasserin aut In The Astronomical Journal IOP Publishing, 2022 165(2023), 3, p 100 (DE-627)312175647 (DE-600)2003104-X 15383881 nnns volume:165 year:2023 number:3, p 100 https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709 kostenfrei https://doi.org/10.3847/1538-3881/acad84 kostenfrei https://doaj.org/toc/1538-3881 Journal toc kostenfrei GBV_USEFLAG_A SYSFLAG_A GBV_DOAJ GBV_ILN_11 GBV_ILN_20 GBV_ILN_22 GBV_ILN_23 GBV_ILN_24 GBV_ILN_31 GBV_ILN_39 GBV_ILN_40 GBV_ILN_60 GBV_ILN_62 GBV_ILN_63 GBV_ILN_65 GBV_ILN_69 GBV_ILN_70 GBV_ILN_73 GBV_ILN_95 GBV_ILN_105 GBV_ILN_110 GBV_ILN_151 GBV_ILN_161 GBV_ILN_170 GBV_ILN_213 GBV_ILN_230 GBV_ILN_285 GBV_ILN_293 GBV_ILN_370 GBV_ILN_602 GBV_ILN_2006 GBV_ILN_2014 GBV_ILN_2088 GBV_ILN_2110 GBV_ILN_2129 GBV_ILN_2522 GBV_ILN_4012 GBV_ILN_4037 GBV_ILN_4112 GBV_ILN_4125 GBV_ILN_4126 GBV_ILN_4249 GBV_ILN_4305 GBV_ILN_4306 GBV_ILN_4307 GBV_ILN_4313 GBV_ILN_4322 GBV_ILN_4323 GBV_ILN_4324 GBV_ILN_4325 GBV_ILN_4335 GBV_ILN_4338 GBV_ILN_4367 GBV_ILN_4700 AR 165 2023 3, p 100
language	English
source	In The Astronomical Journal 165(2023), 3, p 100 volume:165 year:2023 number:3, p 100
sourceStr	In The Astronomical Journal 165(2023), 3, p 100 volume:165 year:2023 number:3, p 100
format_phy_str_mv	Article
institution	findex.gbv.de
topic_facet	Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution Astronomy
isfreeaccess_bool	true
container_title	The Astronomical Journal
authorswithroles_txt_mv	Alexander P. Ji @@aut@@ Joshua D. Simon @@aut@@ Ian U. Roederer @@aut@@ Ekaterina Magg @@aut@@ Anna Frebel @@aut@@ Christian I. Johnson @@aut@@ Ralf S. Klessen @@aut@@ Mattis Magg @@aut@@ Gabriele Cescutti @@aut@@ Mario Mateo @@aut@@ Maria Bergemann @@aut@@ John I. Bailey III @@aut@@
publishDateDaySort_date	2023-01-01T00:00:00Z
hierarchy_top_id	312175647
id	DOAJ089162536
language_de	englisch
fullrecord	<?xml version="1.0" encoding="UTF-8"?><collection xmlns="http://www.loc.gov/MARC21/slim"><record><leader>01000naa a22002652 4500</leader><controlfield tag="001">DOAJ089162536</controlfield><controlfield tag="003">DE-627</controlfield><controlfield tag="005">20230505015857.0</controlfield><controlfield tag="007">cr uuu---uuuuu</controlfield><controlfield tag="008">230505s2023 xx \|\|\|\|\|o 00\| \|\|eng c</controlfield><datafield tag="024" ind1="7" ind2=" "><subfield code="a">10.3847/1538-3881/acad84</subfield><subfield code="2">doi</subfield></datafield><datafield tag="035" ind1=" " ind2=" "><subfield code="a">(DE-627)DOAJ089162536</subfield></datafield><datafield tag="035" ind1=" " ind2=" "><subfield code="a">(DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709</subfield></datafield><datafield tag="040" ind1=" " ind2=" "><subfield code="a">DE-627</subfield><subfield code="b">ger</subfield><subfield code="c">DE-627</subfield><subfield code="e">rakwb</subfield></datafield><datafield tag="041" ind1=" " ind2=" "><subfield code="a">eng</subfield></datafield><datafield tag="050" ind1=" " ind2="0"><subfield code="a">QB1-991</subfield></datafield><datafield tag="100" ind1="0" ind2=" "><subfield code="a">Alexander P. Ji</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="245" ind1="1" ind2="0"><subfield code="a">Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II</subfield></datafield><datafield tag="264" ind1=" " ind2="1"><subfield code="c">2023</subfield></datafield><datafield tag="336" ind1=" " ind2=" "><subfield code="a">Text</subfield><subfield code="b">txt</subfield><subfield code="2">rdacontent</subfield></datafield><datafield tag="337" ind1=" " ind2=" "><subfield code="a">Computermedien</subfield><subfield code="b">c</subfield><subfield code="2">rdamedia</subfield></datafield><datafield tag="338" ind1=" " ind2=" "><subfield code="a">Online-Ressource</subfield><subfield code="b">cr</subfield><subfield code="2">rdacarrier</subfield></datafield><datafield tag="520" ind1=" " ind2=" "><subfield code="a">The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization.</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Dwarf galaxies</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Local Group</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">R-process</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Chemical abundances</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Galaxy chemical evolution</subfield></datafield><datafield tag="653" ind1=" " ind2="0"><subfield code="a">Astronomy</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Joshua D. Simon</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Ian U. Roederer</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Ekaterina Magg</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Anna Frebel</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Christian I. Johnson</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Ralf S. Klessen</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Mattis Magg</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Gabriele Cescutti</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Mario Mateo</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Maria Bergemann</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">John I. Bailey III</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="773" ind1="0" ind2="8"><subfield code="i">In</subfield><subfield code="t">The Astronomical Journal</subfield><subfield code="d">IOP Publishing, 2022</subfield><subfield code="g">165(2023), 3, p 100</subfield><subfield code="w">(DE-627)312175647</subfield><subfield code="w">(DE-600)2003104-X</subfield><subfield code="x">15383881</subfield><subfield code="7">nnns</subfield></datafield><datafield tag="773" ind1="1" ind2="8"><subfield code="g">volume:165</subfield><subfield code="g">year:2023</subfield><subfield code="g">number:3, p 100</subfield></datafield><datafield tag="856" ind1="4" ind2="0"><subfield code="u">https://doi.org/10.3847/1538-3881/acad84</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="856" ind1="4" ind2="0"><subfield code="u">https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="856" ind1="4" ind2="0"><subfield code="u">https://doi.org/10.3847/1538-3881/acad84</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="856" ind1="4" ind2="2"><subfield code="u">https://doaj.org/toc/1538-3881</subfield><subfield code="y">Journal toc</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_USEFLAG_A</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">SYSFLAG_A</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_DOAJ</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_11</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_20</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_22</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_23</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_24</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_31</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_39</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_40</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_60</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_62</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_63</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_65</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_69</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_70</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_73</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_95</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_105</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_110</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_151</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_161</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_170</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_213</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_230</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_285</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_293</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_370</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_602</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2006</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2014</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2088</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2110</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2129</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2522</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4012</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4037</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4112</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4125</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4126</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4249</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4305</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4306</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4307</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4313</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4322</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4323</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4324</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4325</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4335</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4338</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4367</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4700</subfield></datafield><datafield tag="951" ind1=" " ind2=" "><subfield code="a">AR</subfield></datafield><datafield tag="952" ind1=" " ind2=" "><subfield code="d">165</subfield><subfield code="j">2023</subfield><subfield code="e">3, p 100</subfield></datafield></record></collection>
callnumber-first	Q - Science
author	Alexander P. Ji
spellingShingle	Alexander P. Ji misc QB1-991 misc Dwarf galaxies misc Local Group misc R-process misc Chemical abundances misc Galaxy chemical evolution misc Astronomy Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II
authorStr	Alexander P. Ji
ppnlink_with_tag_str_mv	@@773@@(DE-627)312175647
format	electronic Article
delete_txt_mv	keep
author_role	aut aut aut aut aut aut aut aut aut aut aut aut
collection	DOAJ
remote_str	true
callnumber-label	QB1-991
illustrated	Not Illustrated
issn	15383881
topic_title	QB1-991 Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II Dwarf galaxies Local Group R-process Chemical abundances Galaxy chemical evolution
topic	misc QB1-991 misc Dwarf galaxies misc Local Group misc R-process misc Chemical abundances misc Galaxy chemical evolution misc Astronomy
topic_unstemmed	misc QB1-991 misc Dwarf galaxies misc Local Group misc R-process misc Chemical abundances misc Galaxy chemical evolution misc Astronomy
topic_browse	misc QB1-991 misc Dwarf galaxies misc Local Group misc R-process misc Chemical abundances misc Galaxy chemical evolution misc Astronomy
format_facet	Elektronische Aufsätze Aufsätze Elektronische Ressource
format_main_str_mv	Text Zeitschrift/Artikel
carriertype_str_mv	cr
hierarchy_parent_title	The Astronomical Journal
hierarchy_parent_id	312175647
hierarchy_top_title	The Astronomical Journal
isfreeaccess_txt	true
familylinks_str_mv	(DE-627)312175647 (DE-600)2003104-X
title	Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II
ctrlnum	(DE-627)DOAJ089162536 (DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709
title_full	Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II
author_sort	Alexander P. Ji
journal	The Astronomical Journal
journalStr	The Astronomical Journal
callnumber-first-code	Q
lang_code	eng
isOA_bool	true
recordtype	marc
publishDateSort	2023
contenttype_str_mv	txt
author_browse	Alexander P. Ji Joshua D. Simon Ian U. Roederer Ekaterina Magg Anna Frebel Christian I. Johnson Ralf S. Klessen Mattis Magg Gabriele Cescutti Mario Mateo Maria Bergemann John I. Bailey III
container_volume	165
class	QB1-991
format_se	Elektronische Aufsätze
author-letter	Alexander P. Ji
doi_str_mv	10.3847/1538-3881/acad84
author2-role	verfasserin
title_sort	metal mixing in the r-process enhanced ultrafaint dwarf galaxy reticulum ii
callnumber	QB1-991
title_auth	Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II
abstract	The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization.
abstractGer	The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization.
abstract_unstemmed	The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization.
collection_details	GBV_USEFLAG_A SYSFLAG_A GBV_DOAJ GBV_ILN_11 GBV_ILN_20 GBV_ILN_22 GBV_ILN_23 GBV_ILN_24 GBV_ILN_31 GBV_ILN_39 GBV_ILN_40 GBV_ILN_60 GBV_ILN_62 GBV_ILN_63 GBV_ILN_65 GBV_ILN_69 GBV_ILN_70 GBV_ILN_73 GBV_ILN_95 GBV_ILN_105 GBV_ILN_110 GBV_ILN_151 GBV_ILN_161 GBV_ILN_170 GBV_ILN_213 GBV_ILN_230 GBV_ILN_285 GBV_ILN_293 GBV_ILN_370 GBV_ILN_602 GBV_ILN_2006 GBV_ILN_2014 GBV_ILN_2088 GBV_ILN_2110 GBV_ILN_2129 GBV_ILN_2522 GBV_ILN_4012 GBV_ILN_4037 GBV_ILN_4112 GBV_ILN_4125 GBV_ILN_4126 GBV_ILN_4249 GBV_ILN_4305 GBV_ILN_4306 GBV_ILN_4307 GBV_ILN_4313 GBV_ILN_4322 GBV_ILN_4323 GBV_ILN_4324 GBV_ILN_4325 GBV_ILN_4335 GBV_ILN_4338 GBV_ILN_4367 GBV_ILN_4700
container_issue	3, p 100
title_short	Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II
url	https://doi.org/10.3847/1538-3881/acad84 https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709 https://doaj.org/toc/1538-3881
remote_bool	true
author2	Joshua D. Simon Ian U. Roederer Ekaterina Magg Anna Frebel Christian I. Johnson Ralf S. Klessen Mattis Magg Gabriele Cescutti Mario Mateo Maria Bergemann John I. Bailey III
author2Str	Joshua D. Simon Ian U. Roederer Ekaterina Magg Anna Frebel Christian I. Johnson Ralf S. Klessen Mattis Magg Gabriele Cescutti Mario Mateo Maria Bergemann John I. Bailey III
ppnlink	312175647
callnumber-subject	QB - Astronomy
mediatype_str_mv	c
isOA_txt	true
hochschulschrift_bool	false
doi_str	10.3847/1538-3881/acad84
callnumber-a	QB1-991
up_date	2024-07-03T21:37:23.196Z
_version_	1803595434632937472
fullrecord_marcxml	<?xml version="1.0" encoding="UTF-8"?><collection xmlns="http://www.loc.gov/MARC21/slim"><record><leader>01000naa a22002652 4500</leader><controlfield tag="001">DOAJ089162536</controlfield><controlfield tag="003">DE-627</controlfield><controlfield tag="005">20230505015857.0</controlfield><controlfield tag="007">cr uuu---uuuuu</controlfield><controlfield tag="008">230505s2023 xx \|\|\|\|\|o 00\| \|\|eng c</controlfield><datafield tag="024" ind1="7" ind2=" "><subfield code="a">10.3847/1538-3881/acad84</subfield><subfield code="2">doi</subfield></datafield><datafield tag="035" ind1=" " ind2=" "><subfield code="a">(DE-627)DOAJ089162536</subfield></datafield><datafield tag="035" ind1=" " ind2=" "><subfield code="a">(DE-599)DOAJ57b2a0a0aa9c4a76803aa68050dd8709</subfield></datafield><datafield tag="040" ind1=" " ind2=" "><subfield code="a">DE-627</subfield><subfield code="b">ger</subfield><subfield code="c">DE-627</subfield><subfield code="e">rakwb</subfield></datafield><datafield tag="041" ind1=" " ind2=" "><subfield code="a">eng</subfield></datafield><datafield tag="050" ind1=" " ind2="0"><subfield code="a">QB1-991</subfield></datafield><datafield tag="100" ind1="0" ind2=" "><subfield code="a">Alexander P. Ji</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="245" ind1="1" ind2="0"><subfield code="a">Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II</subfield></datafield><datafield tag="264" ind1=" " ind2="1"><subfield code="c">2023</subfield></datafield><datafield tag="336" ind1=" " ind2=" "><subfield code="a">Text</subfield><subfield code="b">txt</subfield><subfield code="2">rdacontent</subfield></datafield><datafield tag="337" ind1=" " ind2=" "><subfield code="a">Computermedien</subfield><subfield code="b">c</subfield><subfield code="2">rdamedia</subfield></datafield><datafield tag="338" ind1=" " ind2=" "><subfield code="a">Online-Ressource</subfield><subfield code="b">cr</subfield><subfield code="2">rdacarrier</subfield></datafield><datafield tag="520" ind1=" " ind2=" "><subfield code="a">The ultrafaint dwarf galaxy Reticulum II was enriched by a single rare and prolific r -process event. The r -process content of Reticulum II thus provides a unique opportunity to study metal mixing in a relic first galaxy. Using multi-object high-resolution spectroscopy with VLT/GIRAFFE and Magellan/M2FS, we identify 32 clear spectroscopic member stars and measure abundances of Mg, Ca, Fe, and Ba where possible. We find ${72}_{-12}^{+10} \% $ of the stars are r -process-enhanced, with a mean $\left\langle [\mathrm{Ba}{\rm{/}}{\rm{H}}]\right\rangle =-1.68\,\pm \,0.07$ and unresolved intrinsic dispersion σ _[Ba/H] <0.20. The homogeneous r -process abundances imply that Ret II’s metals are well mixed by the time the r -enhanced stars form, which simulations have shown requires at least 100 Myr of metal mixing in between bursts of star formation to homogenize. This is the first direct evidence of bursty star formation in an ultrafaint dwarf galaxy. The homogeneous dilution prefers a prompt and high-yield r -process site, such as collapsar disk winds or prompt neutron star mergers. We also find evidence from [Ba/H] and [Mg/Ca] that the r -enhanced stars in Ret II formed in the absence of substantial pristine gas accretion, perhaps indicating that ≈70% of Ret II stars formed after reionization.</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Dwarf galaxies</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Local Group</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">R-process</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Chemical abundances</subfield></datafield><datafield tag="650" ind1=" " ind2="4"><subfield code="a">Galaxy chemical evolution</subfield></datafield><datafield tag="653" ind1=" " ind2="0"><subfield code="a">Astronomy</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Joshua D. Simon</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Ian U. Roederer</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Ekaterina Magg</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Anna Frebel</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Christian I. Johnson</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Ralf S. Klessen</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Mattis Magg</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Gabriele Cescutti</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Mario Mateo</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">Maria Bergemann</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="700" ind1="0" ind2=" "><subfield code="a">John I. Bailey III</subfield><subfield code="e">verfasserin</subfield><subfield code="4">aut</subfield></datafield><datafield tag="773" ind1="0" ind2="8"><subfield code="i">In</subfield><subfield code="t">The Astronomical Journal</subfield><subfield code="d">IOP Publishing, 2022</subfield><subfield code="g">165(2023), 3, p 100</subfield><subfield code="w">(DE-627)312175647</subfield><subfield code="w">(DE-600)2003104-X</subfield><subfield code="x">15383881</subfield><subfield code="7">nnns</subfield></datafield><datafield tag="773" ind1="1" ind2="8"><subfield code="g">volume:165</subfield><subfield code="g">year:2023</subfield><subfield code="g">number:3, p 100</subfield></datafield><datafield tag="856" ind1="4" ind2="0"><subfield code="u">https://doi.org/10.3847/1538-3881/acad84</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="856" ind1="4" ind2="0"><subfield code="u">https://doaj.org/article/57b2a0a0aa9c4a76803aa68050dd8709</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="856" ind1="4" ind2="0"><subfield code="u">https://doi.org/10.3847/1538-3881/acad84</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="856" ind1="4" ind2="2"><subfield code="u">https://doaj.org/toc/1538-3881</subfield><subfield code="y">Journal toc</subfield><subfield code="z">kostenfrei</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_USEFLAG_A</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">SYSFLAG_A</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_DOAJ</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_11</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_20</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_22</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_23</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_24</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_31</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_39</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_40</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_60</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_62</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_63</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_65</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_69</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_70</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_73</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_95</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_105</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_110</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_151</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_161</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_170</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_213</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_230</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_285</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_293</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_370</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_602</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2006</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2014</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2088</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2110</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2129</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_2522</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4012</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4037</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4112</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4125</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4126</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4249</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4305</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4306</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4307</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4313</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4322</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4323</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4324</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4325</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4335</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4338</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4367</subfield></datafield><datafield tag="912" ind1=" " ind2=" "><subfield code="a">GBV_ILN_4700</subfield></datafield><datafield tag="951" ind1=" " ind2=" "><subfield code="a">AR</subfield></datafield><datafield tag="952" ind1=" " ind2=" "><subfield code="d">165</subfield><subfield code="j">2023</subfield><subfield code="e">3, p 100</subfield></datafield></record></collection>
score	7.4008503

Nicht das Richtige dabei?

Schreiben Sie uns!

Metal Mixing in the r-process Enhanced Ultrafaint Dwarf Galaxy Reticulum II

Nicht das Richtige dabei?

Zugang & Verfügbarkeit

Vorhandene Bände

Nicht das Richtige dabei?