Search Publications

Nonparametric reconstruction of interaction in the cosmic dark sector
DOI: 10.1103/PhysRevD.103.123530 Bibcode: 2021PhRvD.103l3530M

Mukherjee, Purba; Banerjee, Narayan

The possibility of a nongravitational interaction between dark matter and dark energy is reconstructed using some recent data sets. The crucial aspect is that the interaction is not parametrized at the outset, but rather reconstructed directly from the data in a nonparametric way. The cosmic chronometer Hubble data, the Pantheon supernova compilat…

2021 Physical Review D
eHST 31
Re-observing the NLS1 galaxy RE J1034+396 - II. New insights on the soft X-ray excess, QPO, and the analogy with GRS 1915+105
DOI: 10.1093/mnras/staa3386 Bibcode: 2021MNRAS.500.2475J

Done, Chris; Ward, Martin; Jin, Chichuan

The active galactic nucleus (AGN) RE J1034+396 displays the most significant X-ray quasi-periodic oscillation (QPO) detected so far. We perform a detailed spectral-timing analysis of our recent simultaneous XMM-Newton, NuSTAR, and Swift observations. We present the energy dependence of the QPO's frequency, rms, coherence, and phase lag, and model …

2021 Monthly Notices of the Royal Astronomical Society
XMM-Newton 31
Thermal and Turbulent Properties of the Warm Neutral Medium in the Solar Neighborhood
DOI: 10.3847/1538-4357/abd108 Bibcode: 2021ApJ...908..186M

Miville-Deschênes, Marc-Antoine; Marchal, Antoine

The transition from the diffuse warm neutral medium (WNM) to the dense cold neutral medium (CNM) is what set the initial conditions to the formation of molecular clouds. The properties of the turbulent cascade in the WNM, essential to describe this radiative condensation process, have remained elusive in part due to the difficulty in mapping out t…

2021 The Astrophysical Journal
Gaia 31
Cepheids with Giant Companions. I. Revealing a Numerous Population of Double-lined Binary Cepheids
DOI: 10.3847/1538-4357/abe7e9 Bibcode: 2021ApJ...910..118P

Anderson, Richard I.; Gieren, Wolfgang; Pietrzyński, Grzegorz +5 more

Masses of classical Cepheids of 3-11 M are predicted by theory but those measured clump between 3.6-5 M. As a result, their mass-luminosity relation is poorly constrained, impeding our understanding of basic stellar physics and the Leavitt Law. All Cepheid masses come from the analysis of 11 binary systems, including only f…

2021 The Astrophysical Journal
Gaia 31
Determining the true mass of radial-velocity exoplanets with Gaia. Nine planet candidates in the brown dwarf or stellar regime and 27 confirmed planets
DOI: 10.1051/0004-6361/202039168 Bibcode: 2021A&A...645A...7K

Lecavelier des Etangs, A.; Vidal-Madjar, A.; Kiefer, F. +3 more

Mass is one of the most important parameters for determining the true nature of an astronomical object. Yet, many published exoplanets lack a measurement of their true mass, in particular those detected as a result of radial-velocity (RV) variations of their host star. For those examples, only the minimum mass, or m sin i, is known, owing to the i…

2021 Astronomy and Astrophysics
Gaia eHST 31
The Carnegie Chicago Hubble Program X: Tip of the Red Giant Branch Distances to NGC 5643 and NGC 1404
DOI: 10.3847/1538-4357/abfe5a Bibcode: 2021ApJ...915...34H

Madore, Barry F.; Freedman, Wendy L.; Beaton, Rachael L. +7 more

The primary goal of the Carnegie Chicago Hubble Program (CCHP) is to calibrate the zero-point of the Type Ia supernova (SN Ia) Hubble Diagram through the use of Population II standard candles. So far, the CCHP has measured direct distances to 11 SNe Ia, and here we increase that number to 15 with two new Tip of the Red Giant Branch (TRGB) distance…

2021 The Astrophysical Journal
eHST 31
A highly non-Keplerian protoplanetary disc. Spiral structure in the gas disc of CQ Tau
DOI: 10.1051/0004-6361/202039469 Bibcode: 2021A&A...648A..19W

Lodato, G.; Testi, L.; Facchini, S. +9 more

Context. In recent years high-angular-resolution observations have revealed that circumstellar discs appear in a variety of shapes with diverse substructures being ubiquitous. This has given rise to the question of whether these substructures are triggered by planet-disc interactions. Besides direct imaging, one of the most promising methods to di…

2021 Astronomy and Astrophysics
Gaia 31
Supernova bounds on axionlike particles coupled with nucleons and electrons
DOI: 10.1103/PhysRevD.104.043016 Bibcode: 2021PhRvD.104d3016C

Calore, Francesca; Carenza, Pierluca; Giannotti, Maurizio +3 more

We investigate the potential of type II supernovae (SNe) to constrain axionlike particles (ALPs) coupled simultaneously to nucleons and electrons. ALPs coupled to nucleons can be efficiently produced in the SN core via nucleon-nucleon bremsstrahlung and, for a wide range of parameters, leave the SN unhindered, producing a large ALP flux. For masse…

2021 Physical Review D
INTEGRAL 31
Revisiting the Cygnus OB associations
DOI: 10.1093/mnras/stab2663 Bibcode: 2021MNRAS.508.2370Q

Quintana, Alexis L.; Wright, Nicholas J.

OB associations play an important role in Galactic evolution, though their origins and dynamics remain poorly studied, with only a small number of systems analysed in detail. In this paper, we revisit the existence and membership of the Cygnus OB associations. We find that of the historical OB associations only Cyg OB2 and OB3 stand out as real gr…

2021 Monthly Notices of the Royal Astronomical Society
Gaia 31
On the compressive nature of turbulence driven by ionizing feedback in the pillars of the Carina Nebula
DOI: 10.1093/mnras/staa3271 Bibcode: 2021MNRAS.500.1721M

Federrath, Christoph; Reiter, Megan; Klaassen, Pamela +2 more

The ionizing radiation of massive stars sculpts the surrounding neutral gas into pillar-like structures. Direct signatures of star formation through outflows and jets are observed in these structures, typically at their tips. Recent numerical simulations have suggested that this star formation could potentially be triggered by photoionizing radiat…

2021 Monthly Notices of the Royal Astronomical Society
Herschel 31