Related papers: Probing fundamental constant evolution with redshi…

We present a search for O I in the spectra of nine 4.9 < z_qso < 6.4 QSOs taken with Keck/HIRES. We detect six systems with N(O I) > 10^13.7 cm^{-2} in the redshift intervals where O I 1302 falls redward of the Ly-alpha forest. Four of…

We determine the Hubble constant $H_0$ precisely ($2.3\%$ uncertainty) in a manner independent of cosmological model through Gaussian process regression, using strong lensing and supernova data. Strong gravitational lensing of a variable…

Context: Narrow-band surveys for Ly-alpha emitters (LAEs) is a powerful tool in detecting high, and very high, redshift galaxies. Even though samples are growing at redshifts z = 3 - 6, the nature of these galaxies is still poorly known.…

We present the first results of a targeted survey carried out with the 305 m Arecibo telescope to detect HI-line emission from galaxies at redshift z>0.16. The targets, selected from the Sloan Digital Sky Survey database, are…

OH is a key molecule in H2O chemistry, a valuable tool for probing physical conditions, and an important contributor to the cooling of shock regions. OH participates in the re-distribution of energy from the protostar towards the…

Observations of fluctuations in the redshifted 21 cm radiation from neautral hydrogen (HI) are perceived to be an important future probe of the universe at high redshifts. Under the assumption that at redshifts z less than 6…

We use observations from the Giant Metrewave Radio Telescope (GMRT) to measure the atomic hydrogen gas content of star-forming galaxies at z = 0.24 (i.e. a look-backtime of ~3 Gyr). The sample of galaxies studied were selected from…

We describe a new estimate of the radio galaxy 1.4 GHz luminosity function and its evolution at intermediate redshifts (z~0.4). Photometric redshifts and color selection have been used to select Bj<23.5 early-type galaxies from the…

The circumgalactic medium (CGM) plays a vital role in galaxy evolution, however, studying the emission from CGM is challenging due to its low surface brightness and the complexities involved in interpreting resonant lines such as…

We present evidence for variations in the fine-structure constant from Keck/HIRES spectra of 143 quasar absorption systems over the redshift range 0.2 < z_abs < 4.2. This includes 15 new systems, mostly at high-z (z_abs > 1.8). Our most…

We present a multiple emission lines study of $\sim$1300 H$\alpha$ emitters (HAEs) at $z \sim 2.3$ in the ZFOURGE survey. In contrast to the traditional spectroscopic method, our sample is selected based on the flux excess in the…

We present the study of arcsecond scale radio continuum and OH line emission of a sample of known OH megamaser galaxies with $z \geq$ 0.15 using archival Very Large Array (VLA) data. And also the results of our pilot Five hundred meter…

We study the properties of star-forming galaxies selected at 610 MHz with the GMRT in a survey covering $\sim$1.86 deg$^2$ down to a noise of $\sim$7.1\,$\mu$Jy / beam. These were identified by combining multiple classification diagnostics:…

Using Hubble Space Telescope and ground-based U through K- band photometry from the Great Observatories Origins Deep Survey (GOODS), we measure the evolution of the luminosity function and luminosity density in the rest-frame optical (UBR)…

We use a combination of deep, high angular resolution imaging data from the CDFS (HST/ACS GOODS survey) and ground based near-IR $K_s$ images to derive the evolution of the galaxy major merger rate in the redshift range $0.2 \leq z \leq…

Recent determinations of the Hubble constant, H_0, at extremely low and very high redshifts based on the cosmic distance ladder (grounded with trigonometric parallaxes) and a cosmological model (applied to Planck 2013 data) respectively,…

Metal line ratios in a sample of 13 quasar spectra obtained with the HIRES spectrograph on the KeckI telescope have been analyzed to characterize the evolution of the metagalactic ionizing flux near a redshift of 3. The evolution of…

An extremely careful separation of the weak metal-line systems relating to the Lyman forest absorbers into individual ``single-phase ionization'' components with accurate parameters has yielded a large sample in the wide redshift range 1.9…

RadioAstron satellite admits in principle a testing the gravitational redshift effect with an accuracy of better than $10^{-5}$. It would surpass the result of Gravity Probe A mission at least an order of magnitude. However, RadioAstron's…

Using deep Keck spectroscopy of Lyman break galaxies selected from infrared imaging data taken with WFC3/IR onboard the Hubble Space Telescope, we present new evidence for a reversal in the redshift-dependent fraction of star forming…