Age gradients in the stellar populations of massive star forming regions based on a new stellar chronometer

Konstantin V. Getman, Eric D. Feigelson, Michael A. Kuhn, Patrick S. Broos, Leisa K. Townsley, Tim Naylor, Matthew S. Povich, Kevin L. Luhman, Gordon P. Garmire

Research output: Contribution to journalArticle

38 Citations (Scopus)

Abstract

A major impediment to understanding star formation in massive star-forming regions (MSFRs) is the absence of a reliable stellar chronometer to unravel their complex star formation histories. We present a new estimation of stellar ages using a new method that employs near-infrared (NIR) and X-ray photometry, Age JX. Stellar masses are derived from X-ray luminosities using the LX -M relation from the Taurus cloud. J-band luminosities are compared to mass-dependent pre-main-sequence (PMS) evolutionary models to estimate ages. Age JX is sensitive to a wide range of evolutionary stages, from disk-bearing stars embedded in a cloud to widely dispersed older PMS stars. The Massive Young Star-Forming Complex Study in Infrared and X-ray (MYStIX) project characterizes 20 OB-dominated MSFRs using X-ray, mid-infrared, and NIR catalogs. The Age JX method has been applied to 5525 out of 31,784 MYStIX Probable Complex Members. We provide a homogeneous set of median ages for over 100 subclusters in 15 MSFRs; median subcluster ages range between 0.5 Myr and 5 Myr. The important science result is the discovery of age gradients across MYStIX regions. The wide MSFR age distribution appears as spatially segregated structures with different ages. The Age JX ages are youngest in obscured locations in molecular clouds, intermediate in revealed stellar clusters, and oldest in distributed populations. The NIR color index J-H, a surrogate measure of extinction, can serve as an approximate age predictor for young embedded clusters.

Original languageEnglish (US)
Article number108
JournalAstrophysical Journal
Volume787
Issue number2
DOIs
StatePublished - Jun 1 2014

Fingerprint

chronometers
massive stars
gradients
stars
x rays
star formation
luminosity
pre-main sequence stars
near infrared
stellar mass
molecular clouds
catalogs
photometry
extinction
histories
color
estimates
predictions
age structure

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

@article{8338ea7cdfff4918b21458f6a1c2fc2c,
title = "Age gradients in the stellar populations of massive star forming regions based on a new stellar chronometer",
abstract = "A major impediment to understanding star formation in massive star-forming regions (MSFRs) is the absence of a reliable stellar chronometer to unravel their complex star formation histories. We present a new estimation of stellar ages using a new method that employs near-infrared (NIR) and X-ray photometry, Age JX. Stellar masses are derived from X-ray luminosities using the LX -M relation from the Taurus cloud. J-band luminosities are compared to mass-dependent pre-main-sequence (PMS) evolutionary models to estimate ages. Age JX is sensitive to a wide range of evolutionary stages, from disk-bearing stars embedded in a cloud to widely dispersed older PMS stars. The Massive Young Star-Forming Complex Study in Infrared and X-ray (MYStIX) project characterizes 20 OB-dominated MSFRs using X-ray, mid-infrared, and NIR catalogs. The Age JX method has been applied to 5525 out of 31,784 MYStIX Probable Complex Members. We provide a homogeneous set of median ages for over 100 subclusters in 15 MSFRs; median subcluster ages range between 0.5 Myr and 5 Myr. The important science result is the discovery of age gradients across MYStIX regions. The wide MSFR age distribution appears as spatially segregated structures with different ages. The Age JX ages are youngest in obscured locations in molecular clouds, intermediate in revealed stellar clusters, and oldest in distributed populations. The NIR color index J-H, a surrogate measure of extinction, can serve as an approximate age predictor for young embedded clusters.",
author = "Getman, {Konstantin V.} and Feigelson, {Eric D.} and Kuhn, {Michael A.} and Broos, {Patrick S.} and Townsley, {Leisa K.} and Tim Naylor and Povich, {Matthew S.} and Luhman, {Kevin L.} and Garmire, {Gordon P.}",
year = "2014",
month = "6",
day = "1",
doi = "10.1088/0004-637X/787/2/108",
language = "English (US)",
volume = "787",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2",

}

Age gradients in the stellar populations of massive star forming regions based on a new stellar chronometer. / Getman, Konstantin V.; Feigelson, Eric D.; Kuhn, Michael A.; Broos, Patrick S.; Townsley, Leisa K.; Naylor, Tim; Povich, Matthew S.; Luhman, Kevin L.; Garmire, Gordon P.

In: Astrophysical Journal, Vol. 787, No. 2, 108, 01.06.2014.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Age gradients in the stellar populations of massive star forming regions based on a new stellar chronometer

AU - Getman, Konstantin V.

AU - Feigelson, Eric D.

AU - Kuhn, Michael A.

AU - Broos, Patrick S.

AU - Townsley, Leisa K.

AU - Naylor, Tim

AU - Povich, Matthew S.

AU - Luhman, Kevin L.

AU - Garmire, Gordon P.

PY - 2014/6/1

Y1 - 2014/6/1

N2 - A major impediment to understanding star formation in massive star-forming regions (MSFRs) is the absence of a reliable stellar chronometer to unravel their complex star formation histories. We present a new estimation of stellar ages using a new method that employs near-infrared (NIR) and X-ray photometry, Age JX. Stellar masses are derived from X-ray luminosities using the LX -M relation from the Taurus cloud. J-band luminosities are compared to mass-dependent pre-main-sequence (PMS) evolutionary models to estimate ages. Age JX is sensitive to a wide range of evolutionary stages, from disk-bearing stars embedded in a cloud to widely dispersed older PMS stars. The Massive Young Star-Forming Complex Study in Infrared and X-ray (MYStIX) project characterizes 20 OB-dominated MSFRs using X-ray, mid-infrared, and NIR catalogs. The Age JX method has been applied to 5525 out of 31,784 MYStIX Probable Complex Members. We provide a homogeneous set of median ages for over 100 subclusters in 15 MSFRs; median subcluster ages range between 0.5 Myr and 5 Myr. The important science result is the discovery of age gradients across MYStIX regions. The wide MSFR age distribution appears as spatially segregated structures with different ages. The Age JX ages are youngest in obscured locations in molecular clouds, intermediate in revealed stellar clusters, and oldest in distributed populations. The NIR color index J-H, a surrogate measure of extinction, can serve as an approximate age predictor for young embedded clusters.

AB - A major impediment to understanding star formation in massive star-forming regions (MSFRs) is the absence of a reliable stellar chronometer to unravel their complex star formation histories. We present a new estimation of stellar ages using a new method that employs near-infrared (NIR) and X-ray photometry, Age JX. Stellar masses are derived from X-ray luminosities using the LX -M relation from the Taurus cloud. J-band luminosities are compared to mass-dependent pre-main-sequence (PMS) evolutionary models to estimate ages. Age JX is sensitive to a wide range of evolutionary stages, from disk-bearing stars embedded in a cloud to widely dispersed older PMS stars. The Massive Young Star-Forming Complex Study in Infrared and X-ray (MYStIX) project characterizes 20 OB-dominated MSFRs using X-ray, mid-infrared, and NIR catalogs. The Age JX method has been applied to 5525 out of 31,784 MYStIX Probable Complex Members. We provide a homogeneous set of median ages for over 100 subclusters in 15 MSFRs; median subcluster ages range between 0.5 Myr and 5 Myr. The important science result is the discovery of age gradients across MYStIX regions. The wide MSFR age distribution appears as spatially segregated structures with different ages. The Age JX ages are youngest in obscured locations in molecular clouds, intermediate in revealed stellar clusters, and oldest in distributed populations. The NIR color index J-H, a surrogate measure of extinction, can serve as an approximate age predictor for young embedded clusters.

UR - http://www.scopus.com/inward/record.url?scp=84900992759&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84900992759&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/787/2/108

DO - 10.1088/0004-637X/787/2/108

M3 - Article

AN - SCOPUS:84900992759

VL - 787

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 108

ER -