Search Publications
"Refsdal" Meets Popper: Comparing Predictions of the Re-appearance of the Multiply Imaged Supernova Behind MACSJ1149.5+2223
Sharon, K.; Diego, J. M.; Zitrin, A. +25 more
Supernova “Refsdal,” multiply imaged by cluster MACS1149.5+2223, represents a rare opportunity to make a true blind test of model predictions in extragalactic astronomy, on a timescale that is short compared to a human lifetime. In order to take advantage of this event, we produced seven gravitational lens models with five independent methods, bas…
INTEGRAL Upper Limits on Gamma-Ray Emission Associated with the Gravitational Wave Event GW150914
Hanlon, L.; Mereghetti, S.; von Kienlin, A. +14 more
Using observations of the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), we place upper limits on the gamma-ray and hard X-ray prompt emission associated with the gravitational wave event GW150914, which was discovered by the LIGO/Virgo Collaboration. The omnidirectional view of the INTEGRAL/SPI-ACS has allowed us to constrain the fra…
Are IRIS Bombs Connected to Ellerman Bombs?
He, Jiansen; Tian, Hui; Xu, Zhi +1 more
Recent observations by the Interface Region Imaging Spectrograph (IRIS) have revealed pockets of hot gas (∼2-8 × 104 K) potentially resulting from magnetic reconnection in the partially ionized lower solar atmosphere (IRIS bombs; IBs). Using joint observations between IRIS and the Chinese New Vacuum Solar Telescope, we have identified 1…
Do the Most Massive Black Holes at z = 2 Grow via Major Mergers?
Jahnke, K.; Silverman, J. D.; Schulze, A. +11 more
The most frequently proposed model for the origin of quasars holds that the high accretion rates seen in luminous active galactic nuclei (AGN) are primarily triggered during major mergers between gas-rich galaxies. While plausible for decades, this model has only begun to be tested with statistical rigor in the past few years. Here, we report on a…
Experimental bounds on collapse models from gravitational wave detectors
Carlesso, Matteo; Bassi, Angelo; Falferi, Paolo +1 more
Wave function collapse models postulate a fundamental breakdown of the quantum superposition principle at the macroscale. Therefore, experimental tests of collapse models are also fundamental tests of quantum mechanics. Here, we compute the upper bounds on the collapse parameters, which can be inferred by the gravitational wave detectors LIGO, LIS…
On-line Tools for Solar Data Compiled at the Debrecen Observatory and Their Extensions with the Greenwich Sunspot Data
Ludmány, A.; Baranyi, T.; Győri, L.
The primary task of the Debrecen Heliophysical Observatory (DHO) has been the most detailed, reliable, and precise documentation of the solar photospheric activity since 1958. This long-term effort resulted in various solar catalogs based on ground-based and space-borne observations. A series of sunspot databases and on-line tools were compiled at…
M31N 2008-12a - The Remarkable Recurrent Nova in M31: Panchromatic Observations of the 2015 Eruption.
Ness, J. -U.; Boumis, P.; Henze, M. +52 more
The Andromeda Galaxy recurrent nova M31N 2008-12a had been observed in eruption 10 times, including yearly eruptions from 2008 to 2014. With a measured recurrence period of {P}{rec}=351+/- 13 days (we believe the true value to be half of this) and a white dwarf very close to the Chandrasekhar limit, M31N 2008-12a has become the leading …
Far-infrared and dust properties of present-day galaxies in the EAGLE simulations
Baes, Maarten; Schaye, Joop; Theuns, Tom +3 more
The Evolution and Assembly of GaLaxies and their Environments (EAGLE) cosmological simulations reproduce the observed galaxy stellar mass function and many galaxy properties. In this work, we study the dust-related properties of present-day EAGLE galaxies through mock observations in the far-infrared and submm wavelength ranges obtained with the 3…
The Story of Supernova “Refsdal” Told by Muse
Treu, T.; Grillo, C.; Balestra, I. +10 more
We present Multi Unit Spectroscopic Explorer (MUSE) observations in the core of the Hubble Frontier Fields (HFF) galaxy cluster MACS J1149.5+2223, where the first magnified and spatially resolved multiple images of supernova (SN) “Refsdal” at redshift 1.489 were detected. Thanks to a Director's Discretionary Time program with the Very Large Telesc…
Spatially Resolved Dust Maps from Balmer Decrements in Galaxies at z ~ 1.4
van Dokkum, Pieter G.; Franx, Marijn; Whitaker, Katherine E. +6 more
We derive average radial gradients in the dust attenuation toward H II regions in 609 galaxies at z ∼ 1.4, using measurements of the Balmer decrement out to r ∼ 3 kpc. The Balmer decrements are derived from spatially resolved maps of Hα and Hβ emission from the 3D-HST survey. We find that with increasing stellar mass M both the normalization and s…