156 citations · 851 across the 36 of their papers we have counts for
36 papers
Non-Primordial Contribution to the Cosmic Microwave Background
Akshith Asundi, Vikram Khaire
The cosmic microwave background is interpreted as relic thermal radiation from the epoch of recombination at z~1090. Recent work by Gjergo & Kroupa (GK25) have challenged this assu…
Uncertainty-Aware Deep Learning for the Ly Forest: CNN-Based Absorber Detection and Characterization
Paryag Sharma, Vikram Khaire, Ting-Yun Cheng +2
The Ly forest is a powerful probe of the intergalactic medium and small-scale matter distribution, but deriving absorber properties traditionally requires computationally expens…
A Measurement of the Thermal and Ionization State of the IGM at
Teng Hu, Vikram Khaire, Joseph F. Hennawi +4
We apply a machine-learning-based inference method that exploits the joint Doppler parameter-column density (b-NHI) distribution from Lya forest decomposition to measure the therma…
High-S/N Quasar Observations with HST/COS: Deep Fields for Spectroscopy
Andrew J. Fox, Jerry Kriss, Philipp Richter +49
Hubble is still in prime observing condition for making transformative discoveries in UV astronomy. In this white paper we describe the science case for a deep (S/N>30) UV spectros…
Discovery of Weak O VI Absorption in Underdense Regions of the Low-Redshift Intergalactic Medium
Sapna Mishra, Vikram Khaire, Romeo Pallikkara +2
We search for weak O VI absorption in the low-redshift intergalactic medium (IGM) using 82 high signal-to-noise quasar spectra from the Cosmic Origins Spectrograph on the Hubble Sp…
Reconstructing galactic feedback history via the Lyman- forest with Habitable Worlds Observatory
Megan T. Tillman, Joseph N. Burchett, Blakesley Burkhart +2
Recent studies have focused on the low- Ly forest as a potential constraint on galactic feedback, as different AGN and stellar feedback models in hydrodynamic simulations pro…
Lyman Limit System with O VI in the Circumgalactic Environment of a Pair of Galaxies
Dheerajkumar Khonde, Purvi Udhwani, Anand Narayanan +3
We report on the analysis of a multiphase Lyman limit system (LLS) at identified towards the background quasar FBQS J0209-0438. The O VI doublet lines associated with t…
The SAP-1 Payload: A Technology Demonstration for Space-Based Microbiology Experiments
A Lokaveer, Vikram Khaire, Thomas Anjana +12
The SSPACE Astrobiology Payload (SAP) series, starting with the SAP-1 project is designed to conduct in-situ microbiology experiments in low earth orbit. This payload series aims t…
Yuti: A General-purpose Transit Simulator for Arbitrary Shaped Objects Orbiting Stars
Ushasi Bhowmick, Vikram Khaire
We present a versatile transit simulator (Yuti) aimed at generating light curves for arbitrarily shaped objects transiting stars. Utilizing a Monte Carlo algorithm, it accurately m…
FLAME: Fitting Ly Absorption lines using Machine learning
Priyanka Jalan, Vikram Khaire, M. Vivek +1
We introduce FLAME, a machine-learning algorithm designed to fit Voigt profiles to HI Lyman-alpha (Ly) absorption lines using deep convolutional neural networks. FLAME integrate…
Searching for the Imprints of AGN Feedback on the Lyman Alpha Forest Around Luminous Red Galaxies
Vikram Khaire, Teng Hu, Joseph F. Hennawi +3
We explore the potential of using the low-redshift Lyman- (Ly) forest surrounding luminous red galaxies (LRGs) as a tool to constrain active galactic nuclei (AGN) feedback mo…
Measurements of the Thermal and Ionization State of the Intergalactic Medium during the Cosmic Afternoon
Teng Hu, Vikram Khaire, Joseph F. Hennawi +4
We perform the first measurement of the thermal and ionization state of the intergalactic medium (IGM) across 0.9 < z < 1.5 using 301 \lya absorption lines fitted from 12 HST STIS…
The Impact of the WHIM on the IGM Thermal State Determined from the Low- Lyman- Forest
Teng Hu, Vikram Khaire, Joseph F. Hennawi +4
At , shock heating caused by large-scale velocity flows and possibly violent feedback from galaxy formation, converts a significant fraction of the cool gas ($T\sim 1…
Can the Low Redshift Lyman Alpha Forest Constrain AGN Feedback Models?
Vikram Khaire, Teng Hu, Joseph F. Hennawi +2
We investigate the potential of low-redshift Lyman alpha (Ly) forest for constraining active galactic nuclei (AGN) feedback models by analyzing the Illustris and IllustrisTNG si…
Measuring the thermal and ionization state of the low- IGM using likelihood free inference
Teng Hu, Vikram Khaire, Joseph F. Hennawi +6
We present a new approach to measure the power-law temperature density relationship and the UV background photoionization rate of the IGM base…
How Robust are the Inferred Density and Metallicity of the Circumgalactic Medium?
Anshuman Acharya, Vikram Khaire
Quantitative estimates of the basic properties of the circumgalactic medium(CGM), such as its density and metallicity, depend on the spectrum of incident UV background radiation. M…
Physical Conditions of Five O VI Absorption Systems Towards PG
Sriram Sankar, Anand Narayanan, Blair D Savage +4
We present the analysis of five O VI absorbers identified across a redshift path of z towards the background quasar PG with information on five consec…
Solar-Metallicity Gas in the Extended Halo of a Galaxy at
Jayadev Pradeep, Sriram Sankar, T. M. Umasree +5
We present the detection and analysis of a weak low-ionization absorber at along the blazar sightline PG~, using spectroscopic data from both /COS and…
Ultraviolet Perspectives on Diffuse Gas in the Largest Cosmic Structures
Joseph N. Burchett, Daisuke Nagai, Iryna Butsky +31
The past decade has seen an explosion of discoveries and new insights into the diffuse gas within galaxies, galaxy clusters, and the filaments composing the Cosmic Web. A new decad…
C IV absorbers tracing cool gas in dense galaxy group/cluster environments
Aditya Manuwal, Anand Narayanan, Sowgat Muzahid +3
We present analysis on three intervening H I-C IV absorption systems tracing gas within galaxy group/cluster environments, identified in the /COS far-UV spectra of the backgro…
Physical conditions in highz optically thin C III absorbers: Origin of cloud sizes and associated correlations
Abhisek Mohapatra, R. Srianand, Vikram Khaire +1
We present detailed photoionization models of well aligned optically thin C III absorption components at . Using our models we estimate density (),…
Effect of non-equilibrium ionization on derived physical conditions of the high- intergalactic medium
Prakash Gaikwad, Raghunathan Srianand, Vikram Khaire +1
Non-equilibrium ionization effects are important in cosmological hydrodynamical simulations but are computationally expensive. We study the effect of non-equilibrium ionization evo…
The Power Spectrum of the Lyman- Forest at z < 0.5
Vikram Khaire, Michael Walther, Joseph F. Hennawi +6
We present new measurements of the flux power-spectrum P(k) of the HI Lyman- forest spanning scales k ~ 0.001-0.1 s/km. These results were derived from 65 far ultraviole…
Detection of Low Metallicity Warm Plasma in a Galaxy Overdensity Environment at z ~ 0.2
Anand Narayanan, Blair D. Savage, Preetish K. Mishra +3
We present results from the analysis of a multiphase O VI - broad Ly-alpha absorber at z = 0.19236 in the HST/COS spectrum of PG 1121+422. The low and intermediate ionization metal…