A5115781258- Galaxies: Formation, Evolution, Phenomena
- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Pulsars and Gravitational Waves Research
- Adaptive optics and wavefront sensing
- Astrophysics and Cosmic Phenomena
- Astronomical Observations and Instrumentation
- CCD and CMOS Imaging Sensors
- Astro and Planetary Science
- Cosmology and Gravitation Theories
- High-pressure geophysics and materials
- History and Developments in Astronomy
- Photovoltaic Systems and Sustainability
- Energy and Environment Impacts
- Social Acceptance of Renewable Energy
- Scientific Research and Discoveries
- Dark Matter and Cosmic Phenomena
- Real-time simulation and control systems
- Radio Astronomy Observations and Technology
- Neutrino Physics Research
- Bacillus and Francisella bacterial research
- History and Theory of Mathematics
Gran Telescopio Canarias (Spain)
2016-2025
Instituto de Astrofísica de Canarias
2016-2025
Universidad de La Laguna
2015-2023
BOKU University
2023
Consejo Superior de Investigaciones Científicas
2017
Nordic Optical Telescope
2012-2015
University of Copenhagen
2012-2014
We report extensive observational data for five of the lowest redshift Super-Luminous Type Ic Supernovae (SL-SNe Ic) discovered to date, namely PTF10hgi, SN2011ke, PTF11rks, SN2011kf and SN2012il. Photometric imaging transients at +50 +230 days after peak combined with host galaxy subtraction reveals a luminous tail phase four these SL-SNe. A high resolution, optical near infrared spectrum from xshooter provides detection broad He I $\lambda$10830 emission line in (+50d) SN2012il, revealing...
ABSTRACT We present ground-based optical photometric monitoring data for NGC 5548, part of an extended multiwavelength reverberation mapping campaign. The light curves have nearly daily cadence from 2014 January to July in nine filters ( BVRI and ugriz ). Combined with ultraviolet the Hubble Space Telescope Swift , we confirm significant time delays between continuum bands as a function wavelength, extending wavelength coverage 1158 Å z band (~9160 Å). find that lags at wavelengths longer...
Abstract We present multi-wavelength analysis of ZTF23abelseb (AT 2023sva), an optically discovered fast-fading (Δmr = 2.2 mag in Δt 0.74 days), luminous (Mr ∼ −30.0 mag) and red (g − r 0.50 transient at z 2.28 with accompanying radio emission. AT 2023sva does not possess a γ-ray burst (GRB) counterpart to isotropic equivalent energy limit Eγ, iso < 1.6 × 1052 erg, determined through searching satellite archives between the last non-detection first detection, making it sixth example...
Long-duration gamma-ray bursts (GRBs) at z < 1 are found in most cases to be accompanied by bright, broad-lined Type Ic supernovae (SNe Ic-BL). The highest-energy GRBs mostly located higher redshifts, where the associated SNe hard detect observationally. Here, we present early and late observations of optical counterpart very energetic GRB 130427A. Despite its moderate redshift, = 0.3399 ± 0.0002, 130427A is high end energy distribution, with an isotropic-equivalent release Eiso ∼ 9.6 × 1053...
The quasar Q0918+1636 (z=3.07) has two intervening high-metallicity Damped Lyman-alpha Absorbers (DLAs) along the line of sight, at redshifts z=2.412 and 2.583. z=2.583 DLA is located a large impact parameter 16.2 kpc, despite this it very high metallicity (consistent with solar), substantial fraction H_2 molecules, dusty as inferred from reddened spectrum background QSO. [M/H]=-0.6 (based on ZnII SiII). In paper we present new observations interesting sightline. HST/WFC3 imaging was...
At low redshift, a handful of gamma-ray bursts (GRBs) have been discovered with peak luminosities ($L_{\rm iso} < 10^{48.5}~\rm{erg\,s}^{-1}$) substantially lower than the average more distant ones > 10^{49.5}~\rm{erg\,s}^{-1}$). The properties several low-luminosity (low-$L$) GRBs indicate that they can be due to shock break-out, as opposed emission from ultrarelativistic jets. Owing this, it is highly debated how both populations are connected, and whether there continuum between them....
Supernova (SN) 2016bdu is an unusual transient resembling SN 2009ip. 2009ip-like events are characterized by a long-lasting phase of erratic variability which ends with two luminous outbursts few weeks apart. The second outburst significantly more (about 3 mag) than the first. In case 2016bdu, first (Event A) reached absolute magnitude M(r) ~ -15.3 mag, while one B) occurred over month later and -18 mag. By inspecting archival data, faint source at position detectable several times in past...
We present the results of a search for red QSOs using selection based on optical imaging from Sloan Digital Sky Survey (SDSS) and near-infrared UKIDSS. Our main goal with is to reddened by foreground dusty absorber galaxies. For sample 58 candidates (including 20 objects fulfilling our criteria that already have spectra in SDSS), 46 (79%) are confirmed be QSOs. The predominantly dust-reddened except handful at redshifts z ≳ 3.5. However, dust most likely located QSO host galaxies (and two,...
We present the analysis and results of a spectroscopic follow-up program mass-selected sample six galaxies at 3 < z 4 using data from Keck-NIRSPEC VLT-Xshooter. confirm > redshifts for half through detection strong nebular emission lines, improve zphot accuracy remainder combination photometry spectra. The modeling emission-line-corrected spectral energy distributions (SEDs) adopting improved confirms very large stellar masses (M_* ~ 1.5-4 x 10^11 Msun) in first 2 Gyrs cosmic history, with...
ABSTRACT During an intensive Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS) UV monitoring campaign of the Seyfert 1 galaxy NGC 5548 performed from 2014 February to July, normally highly correlated far continuum and broad emission line variations decorrelated for ∼60–70 days, starting ∼75 days after first HST /COS observation. Following this anomalous state, flux variability lines returned a more normal state. This transient behavior, characterized by significant deficits in...
We analyze the near-infrared to UV data of 16 quasars with redshifts ranging from 0.71 $<$ $z$ 2.13 investigate dust extinction properties. The sample presented in this work is obtained High $A_V$ Quasar (HAQ) survey. quasar candidates were selected Sloan Digital Sky Survey (SDSS) and UKIRT Infrared Deep (UKIDSS), follow-up spectroscopy was carried out at Nordic Optical Telescope (NOT) New Technology (NTT). To study curves intrinsic quasars, HAQ survey we cases where Small Magellanic Cloud...
We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate temperature structure its accretion disk. The 19 overlapping light curves (1158 9157 angstroms) combine simultaneous HST , Swift and ground-based observations over 180 day period from 2014 January July. Light-curve is interpreted as reverberation response disk irradiation by central time-varying point source. Our model yields inclination, i, T1 at black hole, temperature-radius slope,...
We model the ultraviolet spectra of Seyfert 1 galaxy NGC~5548 obtained with Hubble Space Telescope during 6-month reverberation-mapping campaign in 2014. Our emission from NGC 5548 corrects for overlying absorption and deblends individual lines. Using modeled spectra, we measure response to continuum variations deblended absorption-corrected broad lines, velocity-dependent profiles Ly$\alpha$ C IV, narrow intrinsic features. find that time lags corrected lines are comparable those original...
(Abridged) Long gamma-ray burst (GRB) host galaxies might open a short-cut to the characteristics of typical star-forming throughout history Universe. Due absence near-infrared (NIR) spectroscopy, however, detailed investigations, specifically determination gas-phase metallicity hosts, was largely limited redshifts z < 1 date. Here, we report observations galaxy hosting GRB 080605 at = 1.64 using optical/NIR spectroscopy and high-resolution HST/WFC3 imaging. We avail VLT/X-shooter measure...
Quasi-stellar objects (QSOs) whose spectral energy distributions (SEDs) are reddened by dust either in their host galaxies or intervening absorber to a large degree missed optical color selection criteria like the one used Sloan Digital Sky Survey (SDSS). To overcome this bias against red QSOs, we employ combined and near-infrared selection. In paper, present spectroscopic follow-up campaign of sample candidate QSOs which were selected from SDSS UKIRT Infrared Deep (UKIDSS). The data...
During the Space Telescope and Optical Reverberation Mapping Project (STORM) observations of NGC 5548, continuum emission-line variability became de-correlated during second half 6-month long observing campaign. Here we present Swift Chandra X-ray spectra 5548 obtained as a part The show that excess flux (relative to power-law continuum) in soft band appears before start anomalous behavior, peaks period anomaly, then declines. This is model-independent result suggesting related anomaly. We...
Observations of binary stars containing an accreting black hole or neutron star often show x-ray emission extending to high energies (>10 kilo--electron volts), which is ascribed accretion disk corona energetic particles akin those seen in the solar corona. Despite their ubiquity, physical conditions coronae remain poorly constrained. Using simultaneous infrared, optical, x-ray, and radio observations Galactic system V404 Cygni, showing a rapid synchrotron cooling event its 2015 outburst, we...
We present the results of our photometric and spectroscopic follow-up intermediate-luminosity optical transient AT 2017jfs. At peak, object reaches an absolute magnitude Mg=-15.46+-0.15 mag a bolometric luminosity 5.5x10^41 erg/s. Its light curve has double-peak shape typical Luminous Red Novae (LRNe), with narrow first peak bright in blue bands, while second is longer lasting more luminous red near-infrared (NIR) bands. During spectrum shows continuum emission lines H Fe II. becomes cooler,...
We present geometric and dynamical modeling of the broad line region for multi-wavelength reverberation mapping campaign focused on NGC 5548 in 2014. The dataset includes photometric spectroscopic monitoring optical ultraviolet, covering H$\beta$, C IV, Ly$\alpha$ emission lines. find an extended disk-like H$\beta$ BLR with a mixture near-circular outflowing gas trajectories, while IV BLRs are much less resemble shell-like structures. There is clear radial structure BLR, arising at smaller...
We report the results of a pilot spectroscopic program region at z=5.2 in GOODS-N field containing an overdensity galaxies around well-known submillimeter galaxy HDF850.1. have selected candidate cluster members from optical 25 medium-band photometric catalog project SHARDS (Survey for High-z Absorption Red and Dead Sources). 17 rest-frame UV (LAEs LBGs) with 5.15<z_phot<5.27, candidates to be physically associated overdensity, been observed instrument OSIRIS GranTeCan telescope. 13 out...
We present photometric and spectroscopic data sets for SN 2020pvb, a Type IIn-P supernova (SN) similar to SNe 1994W, 2005cl, 2009kn 2011ht, with precursor outburst detected (PS1 w-band ~ -13.8 mag) around four months before the B-band maximum light. 2020pvb presents relatively bright light curve peaking at M_B = -17.95 +- 0.30 mag plateau lasting least 40 days it went in solar conjunction. After this, object is no longer visible phases > 150 above -12.5 B-band, suggesting that ejecta...
Since the first discovery of a broad-lined type Ic supernova (SN) with long-duration gamma-ray burst (GRB) in 1998, fewer than fifty supernovae (GRB-SNe) have been discovered. The intermediate-luminosity Swift GRB 161219B and its associated SN 2016jca, which occurred at redshift z=0.1475, represents only seventh GRB-SN to discovered within 1 Gpc, hence provides an excellent opportunity investigate observational physical properties these very elusive rare SN. As such, we present optical...
We present the first spectroscopic confirmation of an ultramassive galaxy at redshift using data from Keck-NIRSPEC, VLT-X-shooter, and GTC-Osiris. detect strong [O iii] Lyα emission, weak ii], C iv, He ii, placing C1-23152 a . The modeling emission-line-corrected spectral energy distribution (SED) results in best-fit stellar mass , star formation rate <7 yr−1, negligible dust extinction. stars appear to have formed short intense burst ∼300–500 Myr prior observation epoch, setting this z ∼...
We present the results of a new spectroscopic survey for dusty intervening absorption systems, particularly damped Ly$\alpha$ absorbers (DLAs), towards reddened quasars. The candidate quasars are selected from mid-infrared photometry Wide-field Infrared Survey Explorer combined with optical and near-infrared photometry. Out 1073 candidates, we secure low-resolution spectra 108 using Nordic Optical Telescope on La Palma, Spain. Based spectra, able to classify 100 targets as A large fraction...
New optical photometric, spectrocopic and imaging polarimetry data are combined with publicly available to study some of the physical properties two H-poor superluminous supernovae (SLSN) SN 2021bnw 2021fpl. For each SLSN, best-fit parameters obtained from magnetar model \texttt{MOSFiT} do not depart range parameter on other SLSNe discussed in literature. A spectral analysis \texttt{SYN++} shows that is a W Type, Fast evolver, while 2021fpl 15bn Slow evolver. The at four epochs (+1.8, +20.6,...