Variation of physical properties across the green valley for local galaxies

Abstract

We have selected a sample of nearby galaxies from Sloan Digital Sky Survey Data Release 7 (SDSS DR7) to investigate the physical properties variation from blue cloud to green valley to red sequence. The sample is limited in a narrow range in color-stellar mass diagram. After splitting green valley galaxies into two parts-a bluer green valley (green 1) and a redder one (green 2) and three stellar mass bins, we investigate the physical properties variation across the green valley region. Our main results are as following: (i) The percentages of pure bulge and bulge-dominated/elliptical galaxies increase gradually from blue cloud to red sequence while the percentages of pure disk and disk-dominated/spiral galaxies decrease gradually in all stellar mass bins and different environments; (ii) With the analysis of morphological and structural parameters (e.g., concentration (C) and the stellar mass surface density within the central 1Kpc (Σ 1 )), red galaxies show the most luminous and compact cores than both green valley and blue galaxies while blue galaxies show the opposite behavior in all stellar mass bins. (iii) A strong negative (positive) relationship between bulge-to-total light ratio (B/T) and specific star formation rate (sSFR) (D 4000 ) is found from blue to red galaxies. Our results indicate that the growth of bulge plays an important role when the galaxies change from the blue cloud, to green valley, and to the red sequence.

Stellar populations of a sample of far-infrared AGN and non-AGN green valley galaxies

“…The physical properties of galaxies in the green valley region differ from those in either the blue cloud or the red sequence, indicating intermediate characteristics including their morphological parameters (e.g. Mendez et al 2011 ;Pan, Kong & Fan 2013 ;Gu et al 2018Gu et al , 2019Ge et al 2019 ), luminosity and stellar mass (e.g. Gon c ¸alves et al 2012 ; Phillipps et al 2019 ), age of stellar populations (e.g.…”

“…However, there are also still many inconsistencies found in different studies regarding properties of green valley galaxies, such as their environments (e.g. Pan et al 2013 ;Salim 2014 ;Lee et al 2015 ;Coenda, Mart ínez & Muriel 2018 ;Ge et al 2019 ;Jian et al 2020 ;Das et al 2021 ), fraction (e.g. Schawinski et al 2014 ;Jian et al 2020 ;Das et al 2021 ), or structure (e.g.…”

Properties of green valley galaxies in relation to their selection criteria

“…Between the red sequence and the blue cloud there is a sparsely populated green valley region that has been viewed as the crossroads of galaxy evolution where the galaxies in it are thought to represent the transition population between the blue cloud of star-forming galaxies and the red sequence of quenched and passively evolving galaxies (Schiminovich et al 2007;Pović et al 2012;Salim 2014;Lin et al 2017;Coenda et al 2018;Bryukhareva & Moiseev 2019;Phillipps et al 2019). Several selection criteria have been used to define green valley in order to study the properties of the green galaxy population, using colours such as U -V (Brammer et al 2009), U -B (Mendez et al 2011;Mahoro et al 2017Mahoro et al , 2019, NUV -r (Wyder et al 2007;Lee et al 2015;Coenda et al 2018), g -r (Trayford et al 2015(Trayford et al , 2017Walker et al 2013, Eales et al 2018, u -r (Bremer et al 2018;Eales et al 2018;Kelvin et al 2018;Ge et al 2019;Phillipps et al 2019), specific SFR (sSFR) (Schiminovich et al 2007;Salim et al 2009;Salim 2014;Phillipps et al 2019;Starkenburg et al 2019), and the SFR-stellar mass (M * ) diagram (Noeske et al 2007;Chang et al 2015). Therefore, the study of green valley galaxies provides us crucial clues to connect the red sequence and blue cloud galaxies in terms of their star formation quenching and evolution.…”