scholarly journals Galaxies in 3D across the Universe

2014 ◽  
Vol 10 (S309) ◽  
pp. 17-20
Author(s):  
Denis Burgarella ◽  
Toru Yamada ◽  
Giovanni Fazio ◽  
Marcin Sawicki
Keyword(s):  
Wavelength Range ◽  
High Redshift ◽  
Wide Field ◽  
Ir Camera ◽  
Near Ir ◽  
The Difference ◽  
Survey Strategy ◽  
First Galaxies ◽  
Field Unit ◽  
The Universe

AbstractWISH is a new space science mission concept whose primary goal is to study the first galaxies in the early universe. The primary science goal of the WISH mission is to push the high-redshift frontier beyond the epoch of reionization by utilizing its unique imaging and spectrocopic capabilities and the dedicated survey strategy. WISH will be a 1.5m telescope equipped with a 1000 arcmin2 wide-field Near-IR camera to conduct unique ultra-deep and wide-area sky imaging surveys in the wavelength range 1 - 5 μm. A spectroscopic mode (Integral-Field Unit) in the same Near-IR range and with a field of view of 0.5 - 1 arcmin and a spectral resolution R = 1000 is also planned. The difference between WISH and EUCLID in terms of wavelength range explains why the former concentrates on the reionization period while the latter focuses on the universe at z < 3. WISH and JWST feature different instantaneous fields of view and are therefore also very complementary.

scholarly journals Space Project for Astrophysical and Cosmological Exploration (SPACE), an ESA stand-alone mission and a possible contribution to the Origins Space Telescope

2021 ◽  
Author(s):  
Denis Burgarella ◽  
Andrew Bunker ◽  
Rychard Bouwens ◽  
Laurent Pagani ◽  
Jose Afonso ◽  
...  
Keyword(s):  
Black Holes ◽  
Galaxy Evolution ◽  
High Redshift ◽  
Cosmic Time ◽  
Wide Field ◽  
Unique Region ◽  
Space Telescope ◽  
Near Ir ◽  
Space Project ◽  
First Galaxies

AbstractWe propose a new mission called Space Project for Astrophysical and Cosmological Exploration (SPACE) as part of the ESA long term planning Voyage 2050 programme. SPACE will study galaxy evolution at the earliest times, with the key goals of charting the formation of the heavy elements, measuring the evolution of the galaxy luminosity function, tracing the build-up of stellar mass in galaxies over cosmic time, and finding the first super-massive black holes (SMBHs) to form. The mission will exploit a unique region of the parameter space, between the narrow ultra-deep surveys with HST and JWST, and shallow wide-field surveys such as the Roman Space Telescope and EUCLID, and should yield by far the largest sample of any current or planned mission of very high redshift galaxies at z > 10 which are sufficiently bright for detailed follow-up spectroscopy. Crucially, we propose a wide-field spectroscopic near-IR + mid-IR capability which will greatly enhance our understanding of the first galaxies by detecting and identifying a statistical sample of the first galaxies and the first supermassive black holes, and to chart the metal enrichment history of galaxies in the early Universe – potentially finding signatures of the very first stars to form from metal-free primordial gas. The wide-field and wavelength range of SPACE will also provide us a unique opportunity to study star formation by performing a wide survey of the Milky Way in the near-IR + mid-IR. This science project can be enabled either by a stand-alone ESA-led M mission or by an instrument for an L mission (with ESA and/or NASA, JAXA and other international space agencies) with a wide-field (sub-)millimetre capability at λ > 500 μm.

scholarly journals Stellar populations in the highest redshift galaxies

2015 ◽  
Vol 11 (A29B) ◽  
pp. 197-198
Author(s):  
Andrew J. Bunker
Keyword(s):  
Galaxy Evolution ◽  
High Redshift ◽  
Stellar Populations ◽  
Mass Function ◽  
Initial Mass Function ◽  
Star Forming ◽  
Near Ir ◽  
James Webb Space Telescope ◽  
Large Telescopes ◽  
The Universe

AbstractI discuss stellar populations in galaxies at high redshift (z > 6), in particular the blue rest-frame UV colours which have been detected in recent years through near-IR imaging with HST. These spectral slopes of β < −2 are much more blue than star-forming galaxies at lower redshift, and may suggest less dust obscuration, lower metallicity or perhaps a different initial mass function. I describe current work on the luminosity function of high redshift star- forming galaxies, the evolution of the fraction of strong Lyman-α emitters in this population, and the contribution of the ionizing photon budget from such galaxies towards the reionization of the Universe. I also describe constraints placed by Spitzer/IRAC on stellar populations in galaxies within the first billion years, and look towards future developments in spectroscopy with Extremely Large Telescopes and the James Webb Space Telescope, including the JWST/NIRSpec GTO programme on galaxy evolution at high redshift.

scholarly journals ESO Spectroscopic Facility

2017 ◽  
Vol 13 (S334) ◽  
pp. 242-247
Author(s):  
Luca Pasquini ◽  
B. Delabre ◽  
R. S. Ellis ◽  
J. Marrero ◽  
L. Cavaller ◽  
...  
Keyword(s):  
High Resolution ◽  
Wavelength Range ◽  
Focal Plane ◽  
Working Group ◽  
Field Of View ◽  
High Resolution Spectroscopy ◽  
Wide Field ◽  
Low Resolution ◽  
Field Unit ◽  
Integral Field

AbstractWe present the concept of a novel facility dedicated to massively-multiplexed spectroscopy. The telescope has a very wide field Cassegrain focus optimised for fibre feeding. With a Field of View (FoV) of 2.5 degrees diameter and a 11.4m pupil, it will be the largest etendue telescope. The large focal plane can easily host up to 16.000 fibres. In addition, a gravity invariant focus for the central 10 arc-minutes is available to host a giant integral field unit (IFU). The 3 lenses corrector includes an ADC, and has good performance in the 360-1300 nm wavelength range. The top level science requirements were developed by a dedicated ESO working group, and one of the primary cases is high resolution spectroscopy of GAIA stars and, in general, how our Galaxy formed and evolves. The facility will therefore be equipped with both, high and low resolution spectrographs. We stress the importance of developing the telescope and instrument designs simultaneously. The most relevant R&amp;D aspect is also briefly discussed.

scholarly journals Probing the Cosmic Frontier of Galaxies

2015 ◽  
Vol 11 (A29B) ◽  
pp. 808-811
Author(s):  
Pascal A. Oesch
Keyword(s):  
Galaxy Formation ◽  
Mass Density ◽  
Formation Rate ◽  
Big Bang ◽  
Ir Camera ◽  
Blank Field ◽  
Open Questions ◽  
First Galaxies ◽  
The Big Bang ◽  
The Universe

AbstractUnderstanding when and how the first galaxies formed and what sources reionized the universe are key goals of extragalactic astronomy. Thanks to deep surveys with the powerful WFC3/IR camera on the HST, the observational frontier of galaxy build-up now lies at only ~450 Myr after the Big Bang, at redshifts z ~10-12. In combination with deep data from Spitzer/IRAC we can now probe the evolution of the stellar mass density over 96% of cosmic history. However, detecting and characterizing galaxies at these early epochs is challenging even for HST and the sample sizes at the earliest redshifts are still very small. The Hubble Frontier Fields provide a prime new dataset to improve upon our current, sparse sampling of the UV luminosity function at z>8 from blank fields to answer some of the most pressing open questions. For instance, even the evolution of the cosmic star-formation rate density at z>8 is still debated. While our measurements based on blank field data indicate that galaxies with SFR>0.7 Msol/yr disappear quickly from the cosmic record between z~8 and z~10, other previous results, e.g., from the CLASH survey favor a more moderate decline. Here, we briefly review the recent progress in studying galaxy build-up out to z~10 from the combined blank field and existing Frontier Field datasets and discuss their implications for primordial galaxy formation and cosmic reionization.

scholarly journals The CO universe: modelling CO emission and H2 abundance in cosmological galaxy formation simulations

2020 ◽  
Vol 498 (4) ◽  
pp. 5960-5971
Author(s):  
Shigeki Inoue ◽  
Naoki Yoshida ◽  
Hidenobu Yajima
Keyword(s):  
Galaxy Formation ◽  
High Redshift ◽  
Rotational Transition ◽  
Interstellar Clouds ◽  
Star Forming ◽  
The Difference ◽  
Stellar Masses ◽  
Dust Attenuation ◽  
The Universe ◽  
Co Emission

ABSTRACT We devise a physical model of formation and distribution of molecular gas clouds (MGCs) in galaxies. We use the model to predict the intensities of rotational transition lines of carbon monoxide (CO) and the molecular hydrogen (H2) abundance. Using the outputs of IllustrisTNG cosmological simulations, we populate MGCs of unresolved sizes in individual simulated galaxies, where the effect of the interstellar radiation field with dust attenuation is also taken into account. We then use the publicly available code despotic (Derive the Energetics and SPectra of Optically Thick Interstellar Clouds) to compute the CO line luminosities and H2 densities without assuming the CO-to-H2 conversion factor (αCO). Our method allows us to study the spatial and kinematic structures traced by CO(1–0) and higher transition lines. We compare the CO luminosities and H2 masses with recent observations of galaxies at low and high redshifts. Our model reproduces well the observed CO–luminosity function and the estimated H2 mass in the local UniverseAbout 10 per cent of molecules in the Universe reside in dwarf galaxies with stellar masses lower than 109 M⊙, but the galaxies are generally ‘CO-dark’ and have typically high αCO. Our model predicts generally lower CO line luminosities than observations at redshifts z ≳ 1–2. We argue that the difference can be explained by the highly turbulent structure suggested for the high-redshift star-forming galaxies.

Results of Spatial Structure of Atmosphere Radiation in a Spectral Range (1.5–2) µm Research

2018 ◽  
pp. 7-13
Author(s):  
Anton M. Mishchenko ◽  
Sergei S. Rachkovsky ◽  
Vladimir A. Smolin ◽  
Igor V . Yakimenko
Keyword(s):  
Spatial Structure ◽  
Unmanned Aerial Vehicle ◽  
Wavelength Range ◽  
Spectral Range ◽  
Near Ir ◽  
Optoelectronic Systems ◽  
Aerial Vehicle

Results of experimental studying radiation spatial structure of atmosphere background nonuniformities and of an unmanned aerial vehicle being the detection object are presented. The question on a possibility of its detection using optoelectronic systems against the background of a cloudy field in the near IR wavelength range is also considered.

scholarly journals Testing the evolution of correlations between supermassive black holes and their host galaxies using eight strongly lensed quasars

2020 ◽  
Vol 501 (1) ◽  
pp. 269-280
Author(s):  
Xuheng Ding ◽  
Tommaso Treu ◽  
Simon Birrer ◽  
Adriano Agnello ◽  
Dominique Sluse ◽  
...  
Keyword(s):  
Black Holes ◽  
Hubble Space Telescope ◽  
High Redshift ◽  
Galactic Nuclei ◽  
Host Galaxy ◽  
Wide Field ◽  
Host Galaxies ◽  
Field Surveys ◽  
Instrumental Resolution ◽  
The Moment

ABSTRACT One of the main challenges in using high-redshift active galactic nuclei (AGNs) to study the correlations between the mass of a supermassive black hole ($\mathcal {M}_{\rm BH}$) and the properties of its active host galaxy is instrumental resolution. Strong lensing magnification effectively increases instrumental resolution and thus helps to address this challenge. In this work, we study eight strongly lensed AGNs with deep Hubble Space Telescope imaging, using the lens modelling code lenstronomy to reconstruct the image of the source. Using the reconstructed brightness of the host galaxy, we infer the host galaxy stellar mass based on stellar population models. $\mathcal {M}_{\rm BH}$ are estimated from broad emission lines using standard methods. Our results are in good agreement with recent work based on non-lensed AGNs, demonstrating the potential of using strongly lensed AGNs to extend the study of the correlations to higher redshifts. At the moment, the sample size of lensed AGNs is small and thus they provide mostly a consistency check on systematic errors related to resolution for non-lensed AGNs. However, the number of known lensed AGNs is expected to increase dramatically in the next few years, through dedicated searches in ground- and space-based wide-field surveys, and they may become a key diagnostic of black holes and galaxy co-evolution.

scholarly journals Investigating the properties of a galaxy group at z = 0.6

2020 ◽  
Vol 15 (S359) ◽  
pp. 188-189
Author(s):  
Daniela Hiromi Okido ◽  
Cristina Furlanetto ◽  
Marina Trevisan ◽  
Mônica Tergolina
Keyword(s):  
Large Scale ◽  
The Other ◽  
Numerical Density ◽  
Spectroscopy Data ◽  
Stellar Kinematics ◽  
Galaxy Groups ◽  
The Galaxy ◽  
The Difference ◽  
The Impact ◽  
The Universe

AbstractGalaxy groups offer an important perspective on how the large-scale structure of the Universe has formed and evolved, being great laboratories to study the impact of the environment on the evolution of galaxies. We aim to investigate the properties of a galaxy group that is gravitationally lensing HELMS18, a submillimeter galaxy at z = 2.39. We obtained multi-object spectroscopy data using Gemini-GMOS to investigate the stellar kinematics of the central galaxies, determine its members and obtain the mass, radius and the numerical density profile of this group. Our final goal is to build a complete description of this galaxy group. In this work we present an analysis of its two central galaxies: one is an active galaxy with z = 0.59852 ± 0.00007, while the other is a passive galaxy with z = 0.6027 ± 0.0002. Furthermore, the difference between the redshifts obtained using emission and absorption lines indicates an outflow of gas with velocity v = 278.0 ± 34.3 km/s relative to the galaxy.

scholarly journals New methods for identifying Lyman continuum leakers and reionization-epoch analogues

2020 ◽  
Vol 498 (1) ◽  
pp. 164-180 ◽  
Author(s):  
Harley Katz ◽  
Dominika Ďurovčíková ◽  
Taysun Kimm ◽  
Joki Rosdahl ◽  
Jeremy Blaizot ◽  
...  
Keyword(s):  
Emission Line ◽  
Galaxy Formation ◽  
Dwarf Galaxy ◽  
High Redshift ◽  
Indirect Methods ◽  
High Redshift Galaxies ◽  
Lyman Continuum ◽  
The Universe ◽  
Ionization Parameter ◽  
Redshift Galaxies

ABSTRACT Identifying low-redshift galaxies that emit Lyman continuum radiation (LyC leakers) is one of the primary, indirect methods of studying galaxy formation in the epoch of reionization. However, not only has it proved challenging to identify such systems, it also remains uncertain whether the low-redshift LyC leakers are truly ‘analogues’ of the sources that reionized the Universe. Here, we use high-resolution cosmological radiation hydrodynamics simulations to examine whether simulated galaxies in the epoch of reionization share similar emission line properties to observed LyC leakers at z ∼ 3 and z ∼ 0. We find that the simulated galaxies with high LyC escape fractions (fesc) often exhibit high O32 and populate the same regions of the R23–O32 plane as z ∼ 3 LyC leakers. However, we show that viewing angle, metallicity, and ionization parameter can all impact where a galaxy resides on the O32–fesc plane. Based on emission line diagnostics and how they correlate with fesc, lower metallicity LyC leakers at z ∼ 3 appear to be good analogues of reionization-era galaxies. In contrast, local [S ii]-deficient galaxies do not overlap with the simulated high-redshift LyC leakers on the S ii Baldwin–Phillips–Terlevich (BPT) diagram; however, this diagnostic may still be useful for identifying leakers. We use our simulated galaxies to develop multiple new diagnostics to identify LyC leakers using infrared and nebular emission lines. We show that our model using only [C ii]158 μm and [O iii]88 μm can identify potential leakers from non-leakers from the local Dwarf Galaxy Survey. Finally, we apply this diagnostic to known high-redshift galaxies and find that MACS 1149_JD1 at z = 9.1 is the most likely galaxy to be actively contributing to the reionization of the Universe.

Global registration by optical radiation of lightning discharges on aboard a low-orbit spacecraft

2021 ◽  
Author(s):  
V.S. Chudnovsky ◽  
L.S. Chudnovsky ◽  
Yu.P. Vagin ◽  
A.N. Pleshanov ◽  
K.E. Tyupikov
Keyword(s):  
Wavelength Range ◽  
Optical Radiation ◽  
False Alarms ◽  
Information Flows ◽  
Range Finding ◽  
Global Registration ◽  
Lightning Detection ◽  
Lightning Discharges ◽  
The Difference ◽  
Finding Method

Registration of the coordinates of lightning by their optical radiation has already been implemented on geostationary spacecraft in the wavelength range of 777.4 nm. However, the algorithms for processing the registered signals, as well as the volumes of information flows, have not yet been sufficiently studied. The choice of the sensor for the global registration of optical radiation of lightning on board a low-orbit spacecraft is substantiated. The prospects of using photodiodes in the difference-ranging method for determining coordinates are shown.The characteristics of lightning detection using matrices and LEDs have been studied. The prospects of using photodiodes in the differential-range-finding method for determining coordinates are shown. It is shown that the registration of optical lightning radiation on board the spacecraft by photodiodes provides the characteristics of detection and false alarms of a higher quality compared with the use of CCD matrices.

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