Ultraviolet to Mid‐Infrared Observations of Star‐forming Galaxies at<i>z</i> ∼ 2: Stellar Masses and Stellar Populations

Shapley, Alice E.; Steidel, Charles C.; Erb, Dawn K.; Reddy, Naveen A.; Adelberger, Kurt L.; Pettini, Max; Barmby, P.; Huang, Jia-Sheng

doi:10.1086/429990

Cited by 321 publications

(648 citation statements)

References 52 publications

Supporting

Mentioning

602

Contrasting

Order By: Relevance

“…From their optical and nearinfrared (NIR) studies, Finkelstein et al (2009) found a more robust dust-corrected and de-lensed SFR of 266 ± 74 M yr −1 . Their result confirms that this system is undergoing a very active process of star formation, and shows that the SFR is higher than ∼85% of the high redshift LBGs studied by Shapley et al (2001Shapley et al ( , 2005.…”

Section: Introductionsupporting

confidence: 54%

Very Large Array observations of the 8 o’clock arc lens system: radio emission and a limit on the star-formation rate

Volino

Wucknitz²,

McKean

et al. 2010

A&A

View full text Add to dashboard Cite

Context. The 8 o'clock arc is a gravitationally lensed Lyman break galaxy (LBG) at redshift z = 2.73 that has a star-formation rate (SFR) of ∼270 M yr −1 (derived from optical and near-infrared spectroscopy). Taking the magnification of the system (∼12) and the SFR into account, the expected flux density of any associated radio emission at 1.4 GHz is predicted to be just 0.1 mJy. However, the lens system is found to be coincident with a radio source detected in the NRAO Very Large Array (VLA) Sky Survey with a flux density of ∼5 mJy. If this flux density is attributed to the lensed LBG then it would imply a SFR ∼ 11 000 M yr −1 , in contrast with the optical and near-infrared derived value. Aims. We want to investigate the radio properties of this system, and independently determine the SFR for the LBG from its lensed radio emission. Methods. We have carried out new high resolution imaging with the VLA ain A and B-configurations at 1.4 and 5 GHz. Results. We find that the radio emission is dominated by a radio-loud AGN associated with the lensing galaxy. The radio-jet from the AGN partially covers the lensed arc of the LBG, and we do not detect any radio emission from the unobscured region of the arc down to a 3σ flux-density limit of 108 μJy beam −1 . Conclusions. Using the radio data, we place a limit of ≤750 M yr −1 for the SFR of the LBG, which is consistent with the results from the optical and near-infrared spectroscopy. We expect that the sensitivity of the Expanded VLA will be sufficient to detect many high redshift LBGs that are gravitationally lensed after only a few hours of observing time. The high angular resolution provided by the EVLA will also allow detailed studies of the lensed galaxies and determine if there is radio emission from the lens.

show abstract

Section: Introductionsupporting

confidence: 54%

Very Large Array observations of the 8 o’clock arc lens system: radio emission and a limit on the star-formation rate

Volino

Wucknitz²,

McKean

et al. 2010

A&A

View full text Add to dashboard Cite

show abstract

“…The slope and scatter are expected to be a direct reflection of the similarity in the shape of galaxy SFHs among various models and at various masses (Davé 2008;Noeske et al 2007b). It is worth noting that other z = 2 observations suggest a somewhat large scatter (Shapley et al 2005;Papovich et al 2006), so the observational picture is not entirely settled. Figure 12 shows the SFR of each galaxy of our sample as a function of the corresponding M and the results of various models and observations: analytical models of Buat et al (2008) and Noeske et al (2007a), the semi-analytical Millennium simulations of Kitzbichler & White (2007) used in Buat et al (2008) and observations of Elbaz et al (2007), Daddi et al (2007), and Santini et al (2009).…”

Section: Star Formation Rate and Stellar Massmentioning

confidence: 98%

Population synthesis modelling of luminous infrared galaxies at intermediate redshift

Giovannoli

Buat

Noll

et al. 2010

A&A

View full text Add to dashboard Cite

Context. Luminous InfraRed Galaxies (LIRGs) are particularly important for studying the build-up of the stellar mass from z = 1 to z = 0, and for determining physical properties of these objects at redshift 0.7. LIRGs are now identified as playing a major role in galaxy evolution from z = 1 to 0. The global star formation rate (SFR) at z ∼ 0.7 is mainly produced by LIRGs. Aims. We perform a multiwavelength study of an LIRGs sample in the Extended Chandra Deep Field South at z = 0.7, selected at 24 μm by MIPS onboard Spitzer Space Telescope and detected in 17 filters. Data go from the near-ultraviolet to the mid-infrared. This multiwavelength dataset allows us to place strong constraints on the spectral energy distributions (SEDs) of galaxies, and thus to efficiently derive physical parameters such as the SFR, the total infrared luminosity, attenuation parameters, and star formation history. We distinguish a subsample of galaxies detected at 70 μm, which we compare to the rest of the sample to investigate the relative importance of this wavelength in determining of the physical parameters. An important part of this work is elaboration of a mock catalogue that allows us to have a reliability criterion for the derived parameters. Methods. We studied LIRGs by means of the SED-fitting code CIGALE. At first, this code creates synthetic spectra from the Maraston stellar population models. The stellar population spectra are attenuated by using a synthetic Calzetti-based attenuation law before adding the dust emission as given by the infrared SED library. The originality of CIGALE is that it allows us to perform consistent fits of the dust-affected ultaviolet-to-infrared wavelength range. This technique appears to be a very powerful tool in the case where we can have access to a dataset that is well-sampled over a wide range of wavelengths. Results. We are able to derive a star formation history and to estimate the fraction of infrared luminosity reprocessed by an active galactic nucleus. We study the dust temperatures of our galaxies detected at 70 μm and find them colder than predicted by models. We also study the relation between the SFR and the stellar mass and do not find a tight correlation between either of them, but instead a flat distribution and a large scatter, which is interpreted in terms of variations in star formation history.

show abstract

“…In contrast to the results of Gonzalez et al (2010) and Labbé et al (2010), our relatively young ages resemble those found by Verma et al (2007) and Yabe et al (2009) for z ∼ 5, which are younger than z ∼ 2−3 LBGs (cf. Shapley et al 2001Shapley et al , 2005Sawicki et al 2007;Yabe et al 2009). However, other studies (e.g., Stark et al 2007a;Eyles et al 2007;Stark et al 2009), find relatively old ages at z ∼ 6, and Yabe et al (2009) confirm some of them with their method.…”

Section: Comparison With Lower Redshift Galaxiesmentioning

confidence: 99%

On the physical properties ofz≈6–8 galaxies

Schaerer

Barros

2010

A&A

183

219

View full text Add to dashboard Cite

Aims. We analyse the spectral energy distributions (SEDs) of the most distant galaxies discovered with the Hubble Space telescope and from the COSMOS survey and determine their physical properties, such as stellar age and mass, dust attenuation, and star-formation rate. Methods. We use our SED fitting tool including the effects of nebular emission to analyse three samples of z ∼ 6−8 galaxies with observed magnitudes J AB ∼ 23 to 29. Our models cover a wide parameter space. Results. We find that the physical parameters of most galaxies cover a wide range of acceptable values. Stellar ages, in particular, are not strongly constrained, even for objects detected longward of the Balmer break. As already pointed out earlier, the effects of nebular lines significantly affect the age determinations of star-forming galaxies at z ∼ 6−8. We find no need for stellar populations with extreme metallicities or other non-standard assumptions (IMF, escape fraction) to explain the observed properties of faint z-dropout galaxies. Albeit with large uncertainties, our fit results show indications of dust attenuation in some of the z ≈ 6−8 galaxies, which have best-fit values of A V up to ∼1. Furthermore, we find a possible trend of increasing dust attenuation with galaxy mass, and a relatively large scatter in specific star-formation rates, SFR/M . Conclusions. The physical parameters of very high-z galaxies may be more uncertain than indicated by previous studies. Dust attenuation seems also to be present in some z ≈ 6−8 galaxies, and may be correlated with galaxy mass, as is also the case for SFR.

show abstract

Ultraviolet to Mid‐Infrared Observations of Star‐forming Galaxies atz ∼ 2: Stellar Masses and Stellar Populations

Cited by 321 publications

References 52 publications

Very Large Array observations of the 8 o’clock arc lens system: radio emission and a limit on the star-formation rate

Very Large Array observations of the 8 o’clock arc lens system: radio emission and a limit on the star-formation rate

Population synthesis modelling of luminous infrared galaxies at intermediate redshift

On the physical properties ofz≈6–8 galaxies

Contact Info

Product

Resources

About