PACS-Herschel FIR detections of Lyman-alpha emitters at 2.0<z<3.5

Abstract

In this work we analyze the physical properties of a sample of 56 spectroscopically selected star-forming (SF) Ly$\alpha$ emitting galaxies at 2.0$\lesssim$z$\lesssim$3.5 using both a spectral energy distribution (SED) fitting procedure from rest-frame UV to mid-IR and direct 160$\mu$m observations taken with the Photodetector Array Camera & Spectrometer (PACS) instrument onboard \emph{Herschel Space Observatory}. We define LAEs as those Ly$\alpha$ emitting galaxies whose rest-frame Ly$\alpha$ equivalent widths (Ly$\alpha$ EW${}_{rest-frame}$) are above 20Å, the typical threshold in narrow-band searches. Ly$\alpha$ emitting galaxies with Ly$\alpha$ EW${}_{rest-frame}$ are called non-LAEs. As a result of an individual SED fitting for each object, we find that the studied sample of LAEs contains galaxies with ages mostly below 100Myr and a wide variety of dust attenuations, SFRs, and stellar masses. The heterogeneity in the physical properties is also seen in the morphology, ranging from bulge-like galaxies to highly clumpy systems. In this way, we find that LAEs at 2.0$\lesssim$z$\lesssim$3.5 are very diverse, and do not have a bimodal nature, as suggested in previous works. Furthermore, the main difference between LAEs and non-LAEs is their dust attenuation, because LAEs are not as dusty as non-LAEs. On the FIR side, four galaxies of the sample (two LAEs and two non-LAEs) have PACS-FIR counterparts. Their total IR luminosity place all of them in the ULIRG regime and are all dusty objects, with A${}_{1200}$$\gtrsim$4mag. This is an indication from direct FIR measurements that dust and Ly$\alpha$ emission are not mutually exclusive. This population of red and dusty LAEs is not seen at z$\sim$0.3, suggesting an evolution with redshift of the IR nature of galaxies selected via their Ly$\alpha$ emission.

Accepted for publication in A&A

References in corpus (15)

• GOODS-Herschel: an infrared main sequence for star-forming galaxies
• The Subaru/XMM-Newton Deep Survey (SXDS). IV. Evolution of Lya Emitters from z=3.1 to 5.7 in the 1 deg^2 Field: Luminosity Functions and AGN
• PACS Evolutionary Probe (PEP) - A Herschel Key Program
• On Star Formation Rates and Star Formation Histories of Galaxies out to z ~ 3
• Ly-alpha Emission-Line Galaxies at z = 3.1 in the Extended Chandra Deep Field South
• The GOODS-MUSIC sample: a multicolour catalog of near-IR selected galaxies in the GOODS-South field
• The Zurich Extragalactic Bayesian Redshift Analyzer (ZEBRA) and its first application: COSMOS
• The Great Observatories Origins Deep Survey. VLT/VIMOS Spectroscopy in the GOODS-South Field
• Effects of Dust Geometry in Lyman Alpha Galaxies at z = 4.4
• Lyman Alpha Emitters at Redshift 5.7 in the COSMOS Field
• Lyman alpha emitting galaxies at 0.2 < z < 0.35 from GALEX spectroscopy
• Ly alpha emitting galaxies as early stages in galaxy formation
• Physical properties of z~4 LBGs: differences between galaxies with and without Ly-alpha emission
• Evolution of Lyman Alpha Galaxies: Stellar Populations at z ~ 0.3
• FIR measurements of Ly-$\alpha$ emitters at z$\lesssim$1.0: dust attenuation from PACS-\emph{Herschel}

Cited by in corpus (22)

• An extreme proto-cluster of luminous dusty starbursts in the early Universe
• An excess of dusty starbursts related to the Spiderweb galaxy
• First Spectroscopic Evidence for High Ionization State and Low Oxygen Abundance in Lya Emitters
• The CALYMHA survey: Lya luminosity function and global escape fraction of Lya photons at z=2.23
• Far-infrared surveys of galaxy evolution
• A Comprehensive Study of Ly$\alpha$ Emission in the High-redshift Galaxy Population
• Evidence for Low Extinction in Actively Star Forming Galaxies at z$>$6.5
• The Stellar Mass, Star Formation Rate and Dark Matter Halo Properties of LAEs at $z\sim 2$
• How Do Galaxies trace a large scale structure?: A case study around a massive protocluster at $z=3.13$
• Search for [CII] emission in z=6.5-11 star-forming galaxies
• FIR-detected Lyman break galaxies at z ~ 3: Dust attenuation and dust correction factors at high redshift
• Constraining the Lyman Alpha Escape Fraction with Far-Infrared Observations of Lyman Alpha Emitters
• A Deep Ly$\alpha$ Survey in ECDF-S and COSMOS: I. General Properties of Lyman-alpha Emitters at $z\sim 2$
• First Infrared-based implications for the dust attenuation and star formation of typical Ly$\alpha$ emitters
• The X-ray and radio activity of typical and luminous Lya emitters from z~2 to z~6: evidence for a diverse, evolving population
• The UV to FIR spectral energy distribution of star-forming galaxies in the redshift desert
• Similarities and uniqueness of Ly$\alpha$ emitters among star-forming galaxies at z=2.5
• Lyman break and UV-selected galaxies at z ~ 1: II. PACS-100um/160um FIR detections
• Trident: A three-pronged galaxy survey. I. Lyman alpha emitting galaxies at z~2 in GOODS North
• Lyman break and UV-selected galaxies at $z\sim 1$ I. Stellar populations from ALHAMBRA survey
• SED-inferred properties and morphology of Lyman-break galaxies at $z\sim 1$ in the CDF-S
• Far-infrared observations of dust in Ly$\alpha$ emitters at z=2-6