English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We present deep HST near-IR and Spitzer mid-IR observations of a large sampleof spectroscopically-confirmed galaxies at z >= 6. The sample consists of 51Lyman-alpha emitters (LAEs) at z ~ 5.7, 6.5, and 7.0, and 16 Lyman-breakgalaxies (LBGs) at 5.9 < z < 6.5. The near-IR images were mostly obtained withWFC3 in the F125W and F160W bands, and the mid-IR images were obtained withIRAC in the 3.6um and 4.5um bands. Our galaxies also have deep optical imagingdata from Subaru Suprime-Cam. We utilize the multi-band data and secureredshifts to derive their rest-frame UV properties. These galaxies have steepUV continuum slopes roughly between beta ~ -1.5 and -3.5, with an average valueof beta ~ -2.3, slightly steeper than the slopes of LBGs in previous studies.The slope shows little dependence on UV continuum luminosity except for a fewof the brightest galaxies. We find a statistically significant excess ofgalaxies with slopes around beta ~ -3, suggesting the existence of very youngstellar populations with extremely low metallicity and dust content. Ourgalaxies have moderately strong rest-frame Lyman-alpha equivalent width (EW) ina range of ~10 to ~200 \AA. The star-formation rates are also moderate, from afew to a few tens solar masses per year. The LAEs and LBGs in this sample sharemany common properties, implying that LAEs represent a subset of LBGs withstrong Lyman-alpha emission. Finally, the comparison of the UV luminosityfunctions between LAEs and LBGs suggests that there exists a substantialpopulation of faint galaxies with weak Lyman-alpha emission (EW < 20 \AA) thatcould be the dominant contribution to the total ionizing flux at z >= 6.

astrophysical journal/the astrophysical journal

Physical Properties of Spectroscopically-Confirmed Galaxies at z >= 6.  I. Basic Characteristics of the Rest-Frame UV Continuum and Lyman-alpha  emission