After the Fall: The Dust and Gas in E+A Post-starburst Galaxies

A. Smercina, J. D.T. Smith, D. A. Dale, K. D. French, K. V. Croxall, S. Zhukovska, A. Togi, E. F. Bell, A. F. Crocker, B. T. Draine, T. H. Jarrett, C. Tremonti, Yujin Yang, Ann I Zabludoff

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The traditional picture of post-starburst galaxies as dust- and gas-poor merger remnants, rapidly transitioning to quiescence, has been recently challenged. Unexpected detections of a significant interstellar medium (ISM) in many post-starburst galaxies raise important questions. Are they truly quiescent, and if so, what mechanisms inhibit further star formation? What processes dominate their ISM energetics? We present an infrared spectroscopic and photometric survey of 33 E+A post-starbursts selected by the Sloan Digital Sky Survey, aimed at resolving these questions. We find compact, warm dust reservoirs with high PAH abundances and total gas and dust masses significantly higher than expected from stellar recycling alone. Both polycyclic aromatic hydrocarbon (PAH)/total infrared (TIR) and dust-to-burst stellar mass ratios are seen to decrease with post-burst age, indicative of the accumulating effects of dust destruction and an incipient transition to hot, early-type ISM properties. Their infrared spectral properties are unique, with dominant PAH emission, very weak nebular lines, unusually strong H2 rotational emission, and deep [C ii] deficits. There is substantial scatter among star formation rate (SFR) indicators, and both PAH and TIR luminosities provide overestimates. Even as potential upper limits, all tracers show that the SFR has typically experienced a decline of more than two orders of magnitude since the starburst and that the SFR is considerably lower than expected given both their stellar masses and molecular gas densities. These results paint a coherent picture of systems in which star formation was, indeed, rapidly truncated, but in which the ISM was not completely expelled, and is instead supported against collapse by latent or continued injection of turbulent or mechanical heating. The resulting aging burst populations provide a "high-soft" radiation field that seemingly dominates the E+A galaxies' unusual ISM energetics.

Original languageEnglish (US)
Article number51
JournalAstrophysical Journal
Volume855
Issue number1
DOIs
StatePublished - Mar 1 2018

Fingerprint

starburst galaxies
polycyclic aromatic hydrocarbons
dust
PAH
star formation rate
bursts
gases
gas
stellar mass
star formation
energetics
paints
gas density
molecular gases
recycling
mass ratios
radiation distribution
merger
destruction
tracers

Keywords

  • galaxies: evolution
  • galaxies: interactions
  • galaxies: ISM
  • galaxies: starburst

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Smercina, A., Smith, J. D. T., Dale, D. A., French, K. D., Croxall, K. V., Zhukovska, S., ... Zabludoff, A. I. (2018). After the Fall: The Dust and Gas in E+A Post-starburst Galaxies. Astrophysical Journal, 855(1), [51]. https://doi.org/10.3847/1538-4357/aaafcd

After the Fall : The Dust and Gas in E+A Post-starburst Galaxies. / Smercina, A.; Smith, J. D.T.; Dale, D. A.; French, K. D.; Croxall, K. V.; Zhukovska, S.; Togi, A.; Bell, E. F.; Crocker, A. F.; Draine, B. T.; Jarrett, T. H.; Tremonti, C.; Yang, Yujin; Zabludoff, Ann I.

In: Astrophysical Journal, Vol. 855, No. 1, 51, 01.03.2018.

Research output: Contribution to journalArticle

Smercina, A, Smith, JDT, Dale, DA, French, KD, Croxall, KV, Zhukovska, S, Togi, A, Bell, EF, Crocker, AF, Draine, BT, Jarrett, TH, Tremonti, C, Yang, Y & Zabludoff, AI 2018, 'After the Fall: The Dust and Gas in E+A Post-starburst Galaxies', Astrophysical Journal, vol. 855, no. 1, 51. https://doi.org/10.3847/1538-4357/aaafcd
Smercina A, Smith JDT, Dale DA, French KD, Croxall KV, Zhukovska S et al. After the Fall: The Dust and Gas in E+A Post-starburst Galaxies. Astrophysical Journal. 2018 Mar 1;855(1). 51. https://doi.org/10.3847/1538-4357/aaafcd
Smercina, A. ; Smith, J. D.T. ; Dale, D. A. ; French, K. D. ; Croxall, K. V. ; Zhukovska, S. ; Togi, A. ; Bell, E. F. ; Crocker, A. F. ; Draine, B. T. ; Jarrett, T. H. ; Tremonti, C. ; Yang, Yujin ; Zabludoff, Ann I. / After the Fall : The Dust and Gas in E+A Post-starburst Galaxies. In: Astrophysical Journal. 2018 ; Vol. 855, No. 1.
@article{363cfe3fb06f48579101226866d3da9c,
title = "After the Fall: The Dust and Gas in E+A Post-starburst Galaxies",
abstract = "The traditional picture of post-starburst galaxies as dust- and gas-poor merger remnants, rapidly transitioning to quiescence, has been recently challenged. Unexpected detections of a significant interstellar medium (ISM) in many post-starburst galaxies raise important questions. Are they truly quiescent, and if so, what mechanisms inhibit further star formation? What processes dominate their ISM energetics? We present an infrared spectroscopic and photometric survey of 33 E+A post-starbursts selected by the Sloan Digital Sky Survey, aimed at resolving these questions. We find compact, warm dust reservoirs with high PAH abundances and total gas and dust masses significantly higher than expected from stellar recycling alone. Both polycyclic aromatic hydrocarbon (PAH)/total infrared (TIR) and dust-to-burst stellar mass ratios are seen to decrease with post-burst age, indicative of the accumulating effects of dust destruction and an incipient transition to hot, early-type ISM properties. Their infrared spectral properties are unique, with dominant PAH emission, very weak nebular lines, unusually strong H2 rotational emission, and deep [C ii] deficits. There is substantial scatter among star formation rate (SFR) indicators, and both PAH and TIR luminosities provide overestimates. Even as potential upper limits, all tracers show that the SFR has typically experienced a decline of more than two orders of magnitude since the starburst and that the SFR is considerably lower than expected given both their stellar masses and molecular gas densities. These results paint a coherent picture of systems in which star formation was, indeed, rapidly truncated, but in which the ISM was not completely expelled, and is instead supported against collapse by latent or continued injection of turbulent or mechanical heating. The resulting aging burst populations provide a {"}high-soft{"} radiation field that seemingly dominates the E+A galaxies' unusual ISM energetics.",
keywords = "galaxies: evolution, galaxies: interactions, galaxies: ISM, galaxies: starburst",
author = "A. Smercina and Smith, {J. D.T.} and Dale, {D. A.} and French, {K. D.} and Croxall, {K. V.} and S. Zhukovska and A. Togi and Bell, {E. F.} and Crocker, {A. F.} and Draine, {B. T.} and Jarrett, {T. H.} and C. Tremonti and Yujin Yang and Zabludoff, {Ann I}",
year = "2018",
month = "3",
day = "1",
doi = "10.3847/1538-4357/aaafcd",
language = "English (US)",
volume = "855",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1",

}

TY - JOUR

T1 - After the Fall

T2 - The Dust and Gas in E+A Post-starburst Galaxies

AU - Smercina, A.

AU - Smith, J. D.T.

AU - Dale, D. A.

AU - French, K. D.

AU - Croxall, K. V.

AU - Zhukovska, S.

AU - Togi, A.

AU - Bell, E. F.

AU - Crocker, A. F.

AU - Draine, B. T.

AU - Jarrett, T. H.

AU - Tremonti, C.

AU - Yang, Yujin

AU - Zabludoff, Ann I

PY - 2018/3/1

Y1 - 2018/3/1

N2 - The traditional picture of post-starburst galaxies as dust- and gas-poor merger remnants, rapidly transitioning to quiescence, has been recently challenged. Unexpected detections of a significant interstellar medium (ISM) in many post-starburst galaxies raise important questions. Are they truly quiescent, and if so, what mechanisms inhibit further star formation? What processes dominate their ISM energetics? We present an infrared spectroscopic and photometric survey of 33 E+A post-starbursts selected by the Sloan Digital Sky Survey, aimed at resolving these questions. We find compact, warm dust reservoirs with high PAH abundances and total gas and dust masses significantly higher than expected from stellar recycling alone. Both polycyclic aromatic hydrocarbon (PAH)/total infrared (TIR) and dust-to-burst stellar mass ratios are seen to decrease with post-burst age, indicative of the accumulating effects of dust destruction and an incipient transition to hot, early-type ISM properties. Their infrared spectral properties are unique, with dominant PAH emission, very weak nebular lines, unusually strong H2 rotational emission, and deep [C ii] deficits. There is substantial scatter among star formation rate (SFR) indicators, and both PAH and TIR luminosities provide overestimates. Even as potential upper limits, all tracers show that the SFR has typically experienced a decline of more than two orders of magnitude since the starburst and that the SFR is considerably lower than expected given both their stellar masses and molecular gas densities. These results paint a coherent picture of systems in which star formation was, indeed, rapidly truncated, but in which the ISM was not completely expelled, and is instead supported against collapse by latent or continued injection of turbulent or mechanical heating. The resulting aging burst populations provide a "high-soft" radiation field that seemingly dominates the E+A galaxies' unusual ISM energetics.

AB - The traditional picture of post-starburst galaxies as dust- and gas-poor merger remnants, rapidly transitioning to quiescence, has been recently challenged. Unexpected detections of a significant interstellar medium (ISM) in many post-starburst galaxies raise important questions. Are they truly quiescent, and if so, what mechanisms inhibit further star formation? What processes dominate their ISM energetics? We present an infrared spectroscopic and photometric survey of 33 E+A post-starbursts selected by the Sloan Digital Sky Survey, aimed at resolving these questions. We find compact, warm dust reservoirs with high PAH abundances and total gas and dust masses significantly higher than expected from stellar recycling alone. Both polycyclic aromatic hydrocarbon (PAH)/total infrared (TIR) and dust-to-burst stellar mass ratios are seen to decrease with post-burst age, indicative of the accumulating effects of dust destruction and an incipient transition to hot, early-type ISM properties. Their infrared spectral properties are unique, with dominant PAH emission, very weak nebular lines, unusually strong H2 rotational emission, and deep [C ii] deficits. There is substantial scatter among star formation rate (SFR) indicators, and both PAH and TIR luminosities provide overestimates. Even as potential upper limits, all tracers show that the SFR has typically experienced a decline of more than two orders of magnitude since the starburst and that the SFR is considerably lower than expected given both their stellar masses and molecular gas densities. These results paint a coherent picture of systems in which star formation was, indeed, rapidly truncated, but in which the ISM was not completely expelled, and is instead supported against collapse by latent or continued injection of turbulent or mechanical heating. The resulting aging burst populations provide a "high-soft" radiation field that seemingly dominates the E+A galaxies' unusual ISM energetics.

KW - galaxies: evolution

KW - galaxies: interactions

KW - galaxies: ISM

KW - galaxies: starburst

UR - http://www.scopus.com/inward/record.url?scp=85044219188&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85044219188&partnerID=8YFLogxK

U2 - 10.3847/1538-4357/aaafcd

DO - 10.3847/1538-4357/aaafcd

M3 - Article

AN - SCOPUS:85044219188

VL - 855

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

M1 - 51

ER -