We present six spectroscopically confirmed massive protostructures, spanning
a redshift range of $2.5<z<4.5$ in the Extended Chandra Deep Field South
(ECDFS) field discovered as part of the Charting ...Cluster Construction in VUDS
and ORELSE (C3VO) survey. We identify and characterize these remarkable systems
by applying an overdensity measurement technique on an extensive data
compilation of public and proprietary spectroscopic and photometric
observations in this highly studied extragalactic field. Each of these six
protostructures, i.e., a large scale overdensity (volume $>9000$\thinspace
cMpc$^3$) of more than $2.5\sigma_{\delta}$ above the field density levels at
these redshifts, have a total mass $M_{tot}\ge10^{14.8}M_\odot$ and one or more
highly overdense (overdensity$\thinspace>5\sigma_{\delta}$) peaks. One of the
most complex protostructures discovered is a massive
($M_{tot}=10^{15.1}M_\odot$) system at $z\sim3.47$ that contains six peaks and
55 spectroscopic members. We also discover protostructures at $z\sim3.30$ and
$z\sim3.70$ that appear to at least partially overlap on sky with the
protostructure at $z\sim3.47$, suggesting a possible connection. We
additionally report on the discovery of three massive protostructures at
$z=2.67$, 2.80, and 4.14 and discuss their properties. Finally, we discuss the
relationship between star formation rate and environment in the richest of
these protostructures, finding an enhancement of star formation activity in the
densest regions. The diversity of the protostructures reported here provide an
opportunity to study the complex effects of dense environments on galaxy
evolution over a large redshift range in the early universe.
Motivated by spectroscopic confirmation of three overdense regions in the
COSMOS field at $z\sim3.35$, we analyze the uniquely deep multi-wavelength
photometry and extensive spectroscopy available in ...the field to identify any
further related structure. We construct a three dimensional density map using
the Voronoi tesselation Monte Carlo method and find additional regions of
significant overdensity. Here we present and examine a set of six overdense
structures at $3.20<z<3.45$ in the COSMOS field, the most well characterized of
which, PCl~J0959+0235, has 80 spectroscopically confirmed members and an
estimated mass of $1.35\times 10^{15}$~M$_\odot$, and is modeled to virialize
at $z\sim1.5-2.0$. These structures contain ten overdense peaks with $>5\sigma$
overdensity separated by up to 70 cMpc, suggestive of a proto-supercluster
similar to the Hyperion system at $z\sim2.45$. Upcoming photometric surveys
with JWST such as COSMOS-Web, and further spectroscopic follow-up will enable
more extensive analysis of the evolutionary effects that such an environment
may have on its component galaxies at these early times.
Simulations predict that the galaxy populations inhabiting protoclusters may contribute considerably to the total amount of stellar mass growth of galaxies in the early universe. In this study, we ...test these predictions observationally, focusing on the Taralay protocluster (formerly PCl J1001+0220) at \(z \sim 4.57\) in the COSMOS field. Leveraging data from the Charting Cluster Construction with VUDS and ORELSE (C3VO) survey, we spectroscopically confirmed 44 galaxies within the adopted redshift range of the protocluster (\(4.48 < z < 4.64\)) and incorporate an additional 18 such galaxies from ancillary spectroscopic surveys. Using a density mapping technique, we estimate the total mass of Taralay to be \(\sim 1.7 \times 10^{15}\) M\(_\odot\), sufficient to form a massive cluster by the present day. By comparing the star formation rate density (SFRD) within the protocluster (SFRD\(_\text{pc}\)) to that of the coeval field (SFRD\(_\text{field}\)), we find that SFRD\(_\text{pc}\) surpasses the SFRD\(_\text{field}\) by \(\Delta\)log(SFRD/\(M_\odot\) yr\(^{-1}\) Mpc\(^{-3}\)) = \(1.08 \pm 0.32\) (or \(\sim\) 12\(\times\)). The observed contribution fraction of protoclusters to the cosmic SFRD adopting Taralay as a proxy for typical protoclusters is \(33.5\%^{+8.0\%}_{-4.3\%}\), a value \(\sim\)2\(\sigma\) in excess of the predictions from simulations. Taralay contains three peaks that are \(5\sigma\) above the average density at these redshifts. Their SFRD is \(\sim\)0.5 dex higher than the value derived for the overall protocluster. We show that 68% of all star formation in the protocluster takes place within these peaks, and that the innermost regions of the peaks encase \(\sim 50\%\) of the total star formation in the protocluster. This study strongly suggests that protoclusters drive stellar mass growth in the early universe and that this growth may proceed in an inside-out manner.
We present six spectroscopically confirmed massive protostructures, spanning a redshift range of \(2.5<z<4.5\) in the Extended Chandra Deep Field South (ECDFS) field discovered as part of the ...Charting Cluster Construction in VUDS and ORELSE (C3VO) survey. We identify and characterize these remarkable systems by applying an overdensity measurement technique on an extensive data compilation of public and proprietary spectroscopic and photometric observations in this highly studied extragalactic field. Each of these six protostructures, i.e., a large scale overdensity (volume \(>9000\)\thinspace cMpc\(^3\)) of more than \(2.5\sigma_{\delta}\) above the field density levels at these redshifts, have a total mass \(M_{tot}\ge10^{14.8}M_\odot\) and one or more highly overdense (overdensity\(\thinspace>5\sigma_{\delta}\)) peaks. One of the most complex protostructures discovered is a massive (\(M_{tot}=10^{15.1}M_\odot\)) system at \(z\sim3.47\) that contains six peaks and 55 spectroscopic members. We also discover protostructures at \(z\sim3.30\) and \(z\sim3.70\) that appear to at least partially overlap on sky with the protostructure at \(z\sim3.47\), suggesting a possible connection. We additionally report on the discovery of three massive protostructures at \(z=2.67\), 2.80, and 4.14 and discuss their properties. Finally, we discuss the relationship between star formation rate and environment in the richest of these protostructures, finding an enhancement of star formation activity in the densest regions. The diversity of the protostructures reported here provide an opportunity to study the complex effects of dense environments on galaxy evolution over a large redshift range in the early universe.
Motivated by spectroscopic confirmation of three overdense regions in the COSMOS field at \(z\sim3.35\), we analyze the uniquely deep multi-wavelength photometry and extensive spectroscopy available ...in the field to identify any further related structure. We construct a three dimensional density map using the Voronoi tesselation Monte Carlo method and find additional regions of significant overdensity. Here we present and examine a set of six overdense structures at \(3.20<z<3.45\) in the COSMOS field, the most well characterized of which, PCl~J0959+0235, has 80 spectroscopically confirmed members and an estimated mass of \(1.35\times 10^{15}\)~M\(_\odot\), and is modeled to virialize at \(z\sim1.5-2.0\). These structures contain ten overdense peaks with \(>5\sigma\) overdensity separated by up to 70 cMpc, suggestive of a proto-supercluster similar to the Hyperion system at \(z\sim2.45\). Upcoming photometric surveys with JWST such as COSMOS-Web, and further spectroscopic follow-up will enable more extensive analysis of the evolutionary effects that such an environment may have on its component galaxies at these early times.
A retrospective case-control study was conducted using 46 patients affected by amyotrophic lateral sclerosis and 92 closely matched healthy controls. Cases were ascertained through typical clinical ...and instrumental findings. Putative risk factors (bone fractures or major trauma, exposure to domestic animals, surgical operations, disease among first degree relatives and others) were investigated anamnestically using a standard questionnaire. Using Mantel-Haenzsel estimates of the odds ratio, no association was found between amyotrophic lateral sclerosis and the investigated variables.
ABSTRACT
Motivated by spectroscopic confirmation of three overdense regions in the COSMOS field at z ∼ 3.35, we analyse the uniquely deep multiwavelength photometry and extensive spectroscopy ...available in the field to identify any further related structure. We construct a three-dimensional density map using the Voronoi tesselation Monte Carlo method and find additional regions of significant overdensity. Here, we present and examine a set of six overdense structures at 3.20 < z < 3.45 in the COSMOS field, the most well-characterized of which, PCl J0959 + 0235, has 80 spectroscopically confirmed members and an estimated mass of 1.35 × 1015 M⊙, and is modelled to virialize at z ∼ 1.5−2.0. These structures contain 10 overdense peaks with >5σ overdensity separated by up to 70 cMpc, suggestive of a proto-supercluster similar to the Hyperion system at z ∼ 2.45. Upcoming photometric surveys with JWST such as COSMOS-Web, and further spectroscopic follow-up will enable more extensive analysis of the evolutionary effects that such an environment may have on its component galaxies at these early times.
We investigate of the properties of \(\sim\)2000 Herschel/SPIRE-selected galaxies from \(0<z<4\) using a combination of extensive spectroscopy, deep imaging from CFHT, VLA, Spitzer, XMM-Newton, and ...Herschel, and well-calibrated SED fitting. Herschel galaxies are observed to span a range of stellar masses, colors, and absolute magnitudes equivalent to galaxies undetected in SPIRE. Though many Herschel galaxies appear to be in transition, such galaxies are largely consistent with normal star-forming galaxies when rest-frame colors are utilized. The nature of the star-forming "main sequence" is studied and we warn against adopting this framework unless the main sequence is determined precisely. Herschel galaxies at different total infrared luminosities (\(L_{TIR}\)) are compared. Bluer colors, larger nebular extinctions, and larger contributions from younger stellar populations are observed for galaxies with larger \(L_{TIR}\), suggesting that low-\(L_{TIR}\) galaxies are undergoing rejuvenated starbursts while galaxies with higher \(L_{TIR}\) are forming a larger percentage of their stellar mass. A variety of methods are used to select powerful active galactic nuclei (AGN). Galaxies hosting AGN are observed to be undergoing starbursts more commonly and vigorously than a matched sample of galaxies without powerful AGN and, additionally, the fraction of galaxies with an AGN increases with increasing star formation rate at all redshifts. At all redshifts (\(0<z<4\)) the most prodigious star-forming galaxies are found to contain the highest fraction of powerful AGN. For redshift bins that allow a comparison (\(z>0.5\)), the highest \(L_{TIR}\) galaxies in a given redshift bin are unobserved by SPIRE at subsequently lower redshifts, a trend linked to downsizing. In conjunction with other results, this evidence is used to argue for prevalent AGN-driven quenching in starburst galaxies across cosmic time.
