scholarly journals The galaxy environment of a QSO at z ~ 5.7

2013 ◽  
Vol 9 (S304) ◽  
pp. 341-342
Author(s):  
E. Bañados ◽  
B. P. Venemans ◽  
Fabian Walter ◽  
Jaron Kurk ◽  
Roderik Overzier ◽  
...  
Keyword(s):  
Narrow Band ◽  
Narrow Band Imaging ◽  
High Redshift ◽  
Local Universe ◽  
Lyman Alpha ◽  
The Galaxy ◽  
Massive Halos ◽  
Galaxy Environment ◽  
Lyman Alpha Emitters ◽  
First Time

AbstractHigh-redshift quasars are thought to reside in the most massive halos in the early universe and should therefore be located in fields with overdensities of galaxies, which are expected to evolve into galaxy clusters seen in the local Universe. In Bañados et al. (2013), we used deep narrow-band imaging to study the environment of the z=5.72 quasar ULAS J0203 + 0012. The redshift range probed by our narrow band selection is Δz ~ 0.1. This was the first time that Lyman alpha emitters (LAEs) were searched for near a z ~ 6 quasar, to provide clues on the surroundings of quasars at the end of the epoch of reionization. The main result of this work is that no enhancement of LAEs has been found in the surroundings of ULAS J0203 + 0012. We discuss different explanations and interpretations for this non-detection of a galaxy overdensity.

scholarly journals A Deep Narrow Band Imaging Search for CIVλ1548Å and HeIIλ1640Å Emission from Lyman Alpha Blobs

2013 ◽  
Vol 9 (S304) ◽  
pp. 32-33
Author(s):  
Fabrizio Arrigoni Battaia ◽  
Y. Yang ◽  
J. F. Hennawi ◽  
Y. Matsuda ◽  
T. Yamada ◽  
...  
Keyword(s):  
Surface Brightness ◽  
Narrow Band ◽  
Narrow Band Imaging ◽  
High Redshift ◽  
Radio Galaxies ◽  
Emission Lines ◽  
Lyman Alpha ◽  
Upper Limits ◽  
Narrowband Imaging

AbstractTo study the nature of Lyα blobs (aka LABs), we conduct a deep C IV and He II narrowband imaging survey of 13 Lyα blobs located in SSA22 proto-cluster at z ~ 3.1. We reach the unprecedented sensitivity, 5σ surface brightness limit of 2.1 − 3.4 × 10−18 erg s−1 cm−2 arcsec−2 per 1 arcsec2 aperture for two emission lines. We do not detect any extended C IV and He II emission, placing strong upper limits on the He II/Lyα and C IV/Lyα line ratios. We compare our limits with data in the literature related to the nebulae associated with high-redshift radio galaxies (HzRGs) and quasars, and we recover the data by modeling the LABs as nebulosities powered by a central QSO. For further information see Arrigoni Battaia et al. (2014).

Narrow band imaging in the diagnosis of bladder schistosomiasis

2020 ◽  
Vol 13 (4) ◽  
pp. e233929
Author(s):  
Joachim Jimie ◽  
Margaret Lyttle
Keyword(s):  
White Light ◽  
Narrow Band ◽  
Narrow Band Imaging ◽  
Urinary Schistosomiasis ◽  
Detailed Evaluation ◽  
Characteristic Features ◽  
First Time ◽  
Urine Microscopy ◽  
White Light Imaging ◽  
Multiple Episodes

A 23-year-old man presented to us with multiple episodes of visible haematuria associated with dysuria, but no other symptoms suggestive of infection. His physical examination was completely unremarkable. On detailed evaluation of history, it was noted that he was treated for urinary schistosomiasis as a child in Sudan. A diagnostic flexible cystoscopy, with both white light and narrow band imaging (NBI), was done among other tests as a further diagnostic tool to investigate possible causes. This revealed the characteristic features of bladder schistosomiasis. Urine microscopy for Schistosoma haematobium eggs was negative, and this could have caused the diagnosis to be missed. He was treated with praziquantel for chronic bladder schistosomiasis. This is the first time that the use of NBI as an adjunct to white light imaging in the diagnosis of bladder schistosomiasis has been reported.

scholarly journals Quasar Sightline and Galaxy Evolution (QSAGE) survey – I. The galaxy environment of O vi absorbers up to z = 1.4 around PKS 0232−04

2019 ◽  
Vol 486 (1) ◽  
pp. 21-41 ◽  
Author(s):  
R M Bielby ◽  
J P Stott ◽  
F Cullen ◽  
T M Tripp ◽  
J N Burchett ◽  
...  
Keyword(s):  
Galaxy Evolution ◽  
Near Infrared ◽  
Hubble Space Telescope ◽  
High Redshift ◽  
Star Forming ◽  
The Galaxy ◽  
Circumgalactic Medium ◽  
Galaxy Environment ◽  
Using Data ◽  
Galaxy Population

ABSTRACT We present the first results from a study of O vi absorption around galaxies at z < 1.44 using data from a near-infrared grism spectroscopic Hubble Space Telescope Large Programme, the Quasar Sightline and Galaxy Evolution (QSAGE) survey. QSAGE is the first grism galaxy survey to focus on the circumgalactic medium at z ∼ 1, providing a blind survey of the galaxy population. The galaxy sample is H α flux limited (f(H α) > 2 × 10−17 erg s−1 cm−2) at 0.68 < z < 1.44, corresponding to ≳0.2–0.8 M⊙ yr−1. In this first of 12 fields, we combine the galaxy data with high-resolution STIS and COS spectroscopy of the background quasar to study O vi in the circumgalactic medium. At z ∼ 1, we find O vi absorption systems up to b ∼ 350 kpc (∼4Rvir) from the nearest detected galaxy. Further, we find ${\sim }50{{\ \rm per\ cent}}$ of ≳1 M⊙ yr−1 star-forming galaxies within 2Rvir show no associated O vi absorption to a limit of at least N(O vi) = 1013.9 cm−2. That we detect O vi at such large distances from galaxies and that a significant fraction of star-forming galaxies show no detectable O vi absorption disfavours outflows from ongoing star formation as the primary medium traced by these absorbers. Instead, by combining our own low- and high-redshift data with existing samples, we find tentative evidence for many strong (N(O vi) > 1014 cm−2) O vi absorption systems to be associated with M⋆ ∼ 109.5–10 M⊙ mass galaxies (Mhalo ∼ 1011.5–12 M⊙ dark matter haloes), and infer that they may be tracing predominantly collisionally ionized gas within the haloes of such galaxies.

scholarly journals Jansky VLA S-band view of Hα emitters (HAEs) associated with a protocluster 4C23.56 at z = 2.5

2014 ◽  
Vol 10 (S309) ◽  
pp. 287-288
Author(s):  
Minju Lee ◽  
Kenta Suzuki ◽  
Kotaro Kohno ◽  
Yoichi Tamura ◽  
Daisuke Iono ◽  
...  
Keyword(s):  
Galaxy Formation ◽  
Narrow Band ◽  
Narrow Band Imaging ◽  
Large Array ◽  
Dense Region ◽  
Very Large Array ◽  
Star Forming ◽  
Dust Extinction ◽  
The Galaxy ◽  
Galaxy Populations

AbstractWe present recent results on Karl Jansky Very Large Array (JVLA) deep S-band (2-4 GHz) observation towards a protocluster 4C23.56 at redshift z ∼ 2.5. The protocluster 4C23.56 is known to have a significant over density (∼ 5 times) of star-burst galaxies selected to be Hα line-bright by a Subaru narrow band imaging. Now we have found 25 HAEs associated with the protocluster. These starburst HAEs are likely to become massive ellipticals at z = 0 in a cluster. Various other galaxy populations also reside in this field and the fact makes the field very unique as a tool to understand galaxy formation in a over dense region. Subsequent deep 1100-μm continuum surveys by the ASTE 10-m dish have discovered that several submillimeter bright galaxies (SMGs) coincide with HAEs, suggesting HAEs undergoing dusty starbursts. As star formation rates (SFRs) of HAEs might have been underestimated, we use radio being resistant to dust extinction. We investigate the correlation between SFR1.4 GHz and SFRHα for radio index α = 0.8 to see if the correlation holds for the sources and to check the number of dusty star forming galaxies. Our final results will allow us to evaluate quantitatively how the galaxy formation channel may be different under the condition of over-densities.

scholarly journals The cosmic epoch dependence of environmental effects on size evolution of red-sequence early-type galaxies

2018 ◽  
Vol 617 ◽  
pp. A53 ◽  
Author(s):  
S. Andreon
Keyword(s):  
Growth Rate ◽  
Galaxy Evolution ◽  
High Redshift ◽  
Early Period ◽  
Early Type ◽  
General Field ◽  
The Galaxy ◽  
Size Growth ◽  
Massive Halos ◽  
Red Sequence

This work aims to observationally investigate the history of size growth of early-type galaxies and how the growth depends on cosmic epoch and the mass of the halo in which they are embedded. We carried out a photometric and structural analysis in the rest-frameVband of a mass-selected (logM/M⊙> 10.7) sample of red-sequence early-type galaxies with spectroscopic/grism redshift in the general field up toz= 2 to complement a previous work presenting an identical analysis but in halos 100 times more massive and 1000 times denser. We homogeneously derived sizes (effective radii) fully accounting for the multi-component nature of galaxies and the common presence of isophote twists and ellipticity gradients. By using these mass-selected samples, composed of 170 red-sequence early-type galaxies in the general field and 224 identically selected and analyzed in clusters, we isolate the effect on galaxy sizes of the halo in which galaxies are embedded and its dependence on epoch. We find that the log of the galaxy size at a fixed stellar mass, logM/M⊙= 11, has increased with epoch at a rate twice as fast in the field than in cluster in the last 10 Gyr (0.26 ± 0.03 versus 0.13 ± 0.02 dex per unit redshift). Red-sequence early-type galaxies in the general field reached the size of their cousins in denser environment byz= 0.25 ± 0.13 in spite of being three times smaller atz∼ 2. Data point toward a model where size growth is epoch-independent (i.e., ∂ logre/∂z=c), but with a ratecdepending on environment, ∂c/∂ logMhalo≈ 0.05. Environment determines the growth rate (d logre/dz) at all redshifts, indicating an external origin for the galaxy growth without any clear epoch where it ceases to have an effect. The larger size of early-type galaxies in massive halos at high redshift indicates that their size grew buildup earlier (atz> 2) at an accelerated rate, slowing down at some still unidentifiedz> 2 redshift. Instead, the size growth rate of red-sequence early-type galaxies in low-mass halos is reversed: it proceeds at an increased rate at late epochs after an early period (z> 2) of reduced growth, in agreement with the qualitative hierarchical picture of galaxy evolution. We found similar values of scatter around the mass-size relation independently of environment and epoch, indicating that the amount of dissipation in the system forming the observed galaxy does not vary greatly with epoch or environment.

scholarly journals Into the Ly α jungle: exploring the circumgalactic medium of galaxies at z ∼ 4−5 with MUSE

2020 ◽  
Vol 493 (4) ◽  
pp. 5336-5356
Author(s):  
Richard M Bielby ◽  
Michele Fumagalli ◽  
Matteo Fossati ◽  
Marc Rafelski ◽  
Benjamin Oppenheimer ◽  
...  
Keyword(s):  
Absorption Line ◽  
Surface Brightness ◽  
High Redshift ◽  
Radial Profile ◽  
Clear Correlation ◽  
Star Forming ◽  
Wide Range ◽  
The Galaxy ◽  
Galaxy Environment ◽  
Galaxy Populations

ABSTRACT We present a study of the galaxy environment of nine strong H i + C iv absorption line systems (16.2 < log(N(HI)) < 21.2) spanning a wide range in metallicity at z ∼ 4−5, using MUSE integral field and X-Shooter spectroscopic data collected in a z ≈ 5.26 quasar field. We identify galaxies within a 250 kpc and ±1000 km s−1 window for six out of the nine absorption systems, with two of the absorption line systems showing multiple associated galaxies within the MUSE field of view. The space density of Ly α emitting galaxies (LAEs) around the H i and C iv systems is ≈10−20 times the average sky density of LAEs given the flux limit of our survey, showing a clear correlation between the absorption and galaxy populations. Further, we find that the strongest C iv systems in our sample are those that are most closely aligned with galaxies in velocity space, i.e. within velocities of ±500 km s−1. The two most metal-poor systems lie in the most dense galaxy environments, implying we are potentially tracing gas that is infalling for the first time into star-forming groups at high redshift. Finally, we detect an extended Ly α nebula around the z ≈ 5.26 quasar, which extends up to ≈50 kpc at the surface brightness limit of 3.8 × 10−18 erg s−1 cm−2 arcsec−2. After scaling for surface brightness dimming, we find that this nebula is centrally brighter, having a steeper radial profile than the average for nebulae studied at z ∼ 3 and is consistent with the mild redshift evolution seen from z ≈ 2.

scholarly journals Web of the giant: Spectroscopic confirmation of a large-scale structure around the z = 6.31 quasar SDSS J1030+0524

2020 ◽  
Vol 642 ◽  
pp. L1
Author(s):  
Marco Mignoli ◽  
Roberto Gilli ◽  
Roberto Decarli ◽  
Eros Vanzella ◽  
Barbara Balmaverde ◽  
...  
Keyword(s):  
Black Hole ◽  
Large Scale ◽  
Large Scale Structure ◽  
Scale Structure ◽  
Solar Mass ◽  
Massive Black Holes ◽  
Lyman Alpha ◽  
Peculiar Velocities ◽  
The Galaxy ◽  
Lyman Alpha Emitters

We report on the spectroscopic confirmation of a large-scale structure around the luminous z = 6.31 quasi-stellar object (QSO) SDSS J1030+0524, powered by a one billion solar mass black hole. The structure is populated by at least six members, namely, four Lyman-break galaxies (LBGs), and two Lyman alpha emitters (LAEs). The four LBGs were identified among a sample of 21 i-band dropouts with zAB <  25.5 selected up to projected separations of 5 physical Mpc (15 arcmin) from the QSO. Their redshifts were determined through multi-object spectroscopic observations at 8−10 m class telescopes lasting up to eight hours. The two LAEs were identified in a 6 h VLT/MUSE observation centered on the QSO. The redshifts of the six galaxies cover the range between 6.129−6.355. Assuming that the peculiar velocities are negligible, this range corresponds to radial separations of ±5 physical Mpc from the QSO, that is comparable to the projected scale of the observed LBG distribution on the sky. We conservatively estimate that this structure is significant at a level > 3.5σ and that the level of the galaxy overdensity is at least 1.5−2 within the large volume sampled (∼780 physical Mpc3). The spectral properties of the six member galaxies (Lyα strength and UV luminosity) are similar to those of field galaxies at similar redshifts. This is the first spectroscopic identification of a galaxy overdensity around a supermassive black hole in the first billion years of the Universe. Our finding lends support to the idea that the most distant and massive black holes form and grow within massive (>1012 M⊙) dark matter halos in large-scale structures and that the absence of earlier detections of such systems is likely due to observational limitations.

scholarly journals Secularly powered outflows from AGNs: the dominance of non-merger driven supermassive black hole growth

2019 ◽  
Vol 489 (3) ◽  
pp. 4016-4031 ◽  
Author(s):  
R J Smethurst ◽  
B D Simmons ◽  
C J Lintott ◽  
J Shanahan
Keyword(s):  
Black Hole ◽  
Galaxy Evolution ◽  
Narrow Band ◽  
Narrow Band Imaging ◽  
Black Hole Accretion ◽  
Accretion Rates ◽  
The Galaxy ◽  
Black Hole Growth ◽  
Outflow Rate ◽  
Hole Growth

ABSTRACT Recent observations and simulations have revealed the dominance of secular processes over mergers in driving the growth of both supermassive black holes (SMBHs) and galaxy evolution. Here, we obtain narrow-band imaging of AGN powered outflows in a sample of 12 galaxies with disc-dominated morphologies, whose history is assumed to be merger-free. We detect outflows in 10/12 sources in narrow-band imaging of the $\mathrm{[O\, \small {III}] }$ $5007~\mathring{\rm A}$ emission using filters on the Shane-3m telescope. We calculate a mean outflow rate for these AGNs of $0.95\pm 0.14~\rm {M}_{\odot }~\rm {yr}^{-1}$. This exceeds the mean accretion rate of their SMBHs ($0.054\pm 0.039~\rm {M}_{\odot }~\rm {yr}^{-1}$) by a factor of 18. Assuming that the galaxy must provide at least enough material to power both the AGN and outflow, this gives a lower limit on the average inflow rate of $1.01\pm 0.14~\rm {M}_{\odot }~\rm {yr}^{-1}$, a rate which simulations show can be achieved by bars, spiral arms, and cold accretion. We compare our disc-dominated sample to a sample of nearby AGNs with merger dominated histories and show that the black hole accretion rates in our sample are five times higher (4.2σ) and the outflow rates are five times lower (2.6σ). We suggest that this could be a result of the geometry of the smooth, planar inflow in a secular dominated system, which is both spinning up the black hole to increase accretion efficiency and less affected by feedback from the outflow, than in a merger-driven system with chaotic quasi-spherical inflows. This work provides further evidence that secular processes are sufficient to fuel SMBH growth.

scholarly journals Results from Searches for High-Redshift Galaxies around Damped Lyα Systems

1996 ◽  
Vol 171 ◽  
pp. 291-294
Author(s):  
S. J. Warren ◽  
P. Møller
Keyword(s):  
Narrow Band ◽  
Narrow Band Imaging ◽  
High Redshift ◽  
Neutral Hydrogen ◽  
The Other ◽  
High Redshift Galaxies ◽  
Groups Of Galaxies ◽  
Damped Systems ◽  
The Universe ◽  
Redshift Galaxies

There was not much said at this conference about the damped Lyα absorbers, yet locally and at high redshift nearly all the neutral hydrogen in the Universe lies in the damped systems, so they may have much to tell us about when and how galaxies formed. This talk is concerned with the results of narrow-band imaging searches for Lyα emission from, and around, damped Lyα absorbers. There have been many such searches, but very few detections. Here we concentrate on two groups of galaxies at high redshift, z > 2, found by this technique. One of these is a recent discovery (Francis et al. 1995), and for the other we discuss some new observations (Warren and Møller 1995). A study of these two groups provides some clues to the nature of the damped absorbers at high redshift, and the rôle they play in the formation of galaxies.

Sign in / Sign up

Export Citation Format

Share Document