RAS_WEB (Page 4,426)

The whole picture of the large-scale structure of the CL1604 supercluster at z$sim$0.9. (arXiv:1905.13437v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Hayashi_M/0/1/0/all/0/1">Masao Hayashi</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Koyama_Y/0/1/0/all/0/1">Yusei Koyama</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kodama_T/0/1/0/all/0/1">Tadayuki Kodama</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Komiyama_Y/0/1/0/all/0/1">Yutaka Komiyama</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lin_Y/0/1/0/all/0/1">Yen-Ting Lin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Miyazaki_S/0/1/0/all/0/1">Satoshi Miyazaki</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shimakawa_R/0/1/0/all/0/1">Rhythm Shimakawa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Suzuki_T/0/1/0/all/0/1">Tomoko L. Suzuki</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Tanaka_I/0/1/0/all/0/1">Ichi Tanaka</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yamamoto_M/0/1/0/all/0/1">Moegi Yamamoto</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Yamamoto_N/0/1/0/all/0/1">Naoaki Yamamoto</a> We present the large-scale structure over more than 50 comoving Mpc scale at z $sim$ 0.9 where the CL1604 supercluster, which is one of the largest structures ever known at high redshifts, is embedded. The wide-field deep imaging survey by the Subaru Strategic Program with Hyper Suprime-Cam reveals that the already-known CL1604 supercluster is a mereRead More →

Astrophysics in Strong Electromagnetic Fields and Laboratory Astrophysics. (arXiv:1905.13439v1 [gr-qc]) <a href="http://arxiv.org/find/gr-qc/1/au:+Kim_S/0/1/0/all/0/1">Sang Pyo Kim</a> Recent observations of gravitational waves from binary mergers of black holes or neutron stars and the rapid development of ultra-intense lasers lead strong field physics to a frontier of new physics in the 21st century. Strong gravity phenomena are most precisely described by general relativity, and lasers that are described by another most precisely tested quantum electrodynamics (QED) can be focused into a tiny area in a short period through the chirped pulse amplification and generate extremely high intensity electromagnetic (EM) fields beyond the conventional methods. It is physically interesting toRead More →

Earth’s Minimoons: Opportunities for Science and Technology. (arXiv:1905.13457v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Jedicke_R/0/1/0/all/0/1">Robert Jedicke</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bolin_B/0/1/0/all/0/1">Bryce T. Bolin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bottke_W/0/1/0/all/0/1">William F. Bottke</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chyba_M/0/1/0/all/0/1">Monique Chyba</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fedorets_G/0/1/0/all/0/1">Grigori Fedorets</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Granvik_M/0/1/0/all/0/1">Mikael Granvik</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jones_L/0/1/0/all/0/1">Lynne Jones</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Urrutxua_H/0/1/0/all/0/1">Hodei Urrutxua</a> (modified from published version) Twelve years ago the Catalina Sky Survey discovered Earth’s first known natural geocentric object other than the Moon, a few-meter diameter asteroid designated 2006 RH120. Despite significant improvements in ground-based telescope and detector technology in the past decade the asteroid surveys have not discovered another temporarily-captured orbiter (TCO; colloquially known as minimoons). Within a few years the Large Synoptic Survey Telescope (LSST) will either begin toRead More →

The Orbit and Size-Frequency Distribution of Long Period Comets Observed by Pan-STARRS1. (arXiv:1905.13458v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Boe_B/0/1/0/all/0/1">Benjamin Boe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jedicke_R/0/1/0/all/0/1">Robert Jedicke</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Meech_K/0/1/0/all/0/1">Karen J. Meech</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wiegert_P/0/1/0/all/0/1">Paul Wiegert</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Weryk_R/0/1/0/all/0/1">Robert J. Weryk</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Chambers_K/0/1/0/all/0/1">K. C. Chambers</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Denneau_L/0/1/0/all/0/1">L. Denneau</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kaiser_N/0/1/0/all/0/1">N. Kaiser</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kudritzki_R/0/1/0/all/0/1">R. P. Kudritzki</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Magnier_E/0/1/0/all/0/1">E. A. Magnier</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Wainscoat_R/0/1/0/all/0/1">R. J. Wainscoat</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Waters_C/0/1/0/all/0/1">C. Waters</a> We introduce a new technique to estimate the comet nuclear size frequency distribution (SFD) that combines a cometary activity model with a survey simulation and apply it to 150 long period comets (LPC) detected by the Pan-STARRS1 near-Earth object survey. The debiased LPC size-frequency distribution is in agreement withRead More →

Gravitational Waves from Peaks. (arXiv:1905.13459v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Luca_V/0/1/0/all/0/1">V. De Luca</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Desjacques_V/0/1/0/all/0/1">V. Desjacques</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Franciolini_G/0/1/0/all/0/1">G. Franciolini</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Riotto_A/0/1/0/all/0/1">A. Riotto</a> We discuss a novel mechanism to generate gravitational waves in the early universe. A standard way to produce primordial black holes is to enhance at small-scales the overdensity perturbations generated during inflation. The latter, upon horizon re-entry, collapse into black holes. They must be sizeable enough and are therefore associated to rare peaks. There are however less sizeable and much less rare overdensity peaks which do not end up forming primordial black holes and have a non-spherical shape. Upon collapse, they possess a time-dependent non-vanishing massRead More →

Photodesorption of water ice from dust grains and thermal desorption of cometary ices studied by the INSIDE experiment. (arXiv:1905.13465v1 [astro-ph.IM]) <a href="http://arxiv.org/find/astro-ph/1/au:+Potapov_A/0/1/0/all/0/1">Alexey Potapov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jager_C/0/1/0/all/0/1">Cornelia J&#xe4;ger</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Henning_T/0/1/0/all/0/1">Thomas Henning</a> A new experimental set-up INterStellar Ice-Dust Experiment (INSIDE), was designed for studying cosmic grain analogues represented by ice-coated carbon- and silicate-based dust grains. In the new instrument, we can simulate physical and chemical conditions prevailing in interstellar and circumstellar environments. The set-up combines ultrahigh vacuum and low temperature conditions with infrared spectroscopy and mass spectrometry. Using INSIDE, we plan to investigate physical and chemical processes, such as adsorption, desorption, and formation of molecules, on the surfaceRead More →

Evidence of surface catalytic effect on cosmic dust grain analogues: the ammonia and carbon dioxide surface reaction. (arXiv:1905.13471v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Potapov_A/0/1/0/all/0/1">Alexey Potapov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Theule_P/0/1/0/all/0/1">Patrice Theul&#xe9;</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Jager_C/0/1/0/all/0/1">Cornelia J&#xe4;ger</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Henning_T/0/1/0/all/0/1">Thomas Henning</a> Surface chemistry on cosmic dust grains plays an important role in the formation of molecules at low temperatures in the interstellar and circumstellar environments. For the first time, we experimentally put in evidence the catalytic role of dust surfaces using the thermal reaction CO2 + 2NH3 = NH4+NH2COO-, which is also a proxy of radical-radical reactions. Nanometre-sized amorphous silicate and carbon grains produced in our laboratory were used as grain analogues. Surface catalysis onRead More →

Baryon-Dark matter interaction in presence of magnetic fields in light of EDGES signal. (arXiv:1905.13486v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Bhatt_J/0/1/0/all/0/1">Jitesh R. Bhatt</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Natwariya_P/0/1/0/all/0/1">Pravin Kumar Natwariya</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Nayak_A/0/1/0/all/0/1">Alekha C. Nayak</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pandey_A/0/1/0/all/0/1">Arun Kumar Pandey</a> The Experiment to Detect the Global Epoch of reionization Signature (EDGES) collaboration has reported an excess absorption dip in the 21 cm signal during cosmic dawn era. The stronger than expected 21 absorption signal indicates that gas was much cooler than the standard cosmological prediction. The observed 21-cm signal can be explained by decreasing the gas temperature via baryon-DM interaction. In this work, we study the temperature evolution of the gas and Dark MatterRead More →

Follow-up procedure for gravitational wave searches from isolated neutron stars using the time-domain $mathcal{F}$-statistic method. (arXiv:1905.13488v1 [astro-ph.IM]) <a href="http://arxiv.org/find/astro-ph/1/au:+Sieniawska_M/0/1/0/all/0/1">Magdalena Sieniawska</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Bejger_M/0/1/0/all/0/1">Micha&#x142; Bejger</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Krolak_A/0/1/0/all/0/1">Andrzej Kr&#xf3;lak</a> Among promising sources of gravitational waves are long-lived nearly periodic signals produced by rotating, asymmetric neutron stars. Depending on the astrophysical scenario, the sources of asymmetry may have thermal, viscous, elastic and/or magnetic origin. In this work we introduce a follow-up procedure for an all-sky search for gravitational wave signals from rotating neutron stars. The procedure denoted as texttt{Followup} implements matched-filtering $mathcal{F}$-statistic method. We describe data analysis methods and algorithms used in the procedure. We present tests of theRead More →

Probing gaseous halos of galaxies with radio jets. (arXiv:1905.13506v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Krause_M/0/1/0/all/0/1">Martin G. H. Krause</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hardcastle_M/0/1/0/all/0/1">Martin J. Hardcastle</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shabala_S/0/1/0/all/0/1">Stanislav S. Shabala</a> Gaseous halos play a key role for understanding inflow, feedback and the overall baryon budget in galaxies. Literature models predict transitions of the state of the gaseous halo between cold and hot accretion, winds, fountains and hydrostatic halos at certain galaxy masses. Since luminosities of radio AGN are sensitive to halo densities, any significant transition would be expected to show up in the radio luminosities of large samples of galaxies. The Low Frequency Array (LOFAR) Two Metre Sky Survey (LoTSS) has indeedRead More →

Magnetic activities on active solar-type stars. (arXiv:1905.13512v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Karmakar_S/0/1/0/all/0/1">Subhajeet Karmakar</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pandey_J/0/1/0/all/0/1">Jeewan C. Pandey</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Naik_S/0/1/0/all/0/1">Sachindra Naik</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Savanov_I/0/1/0/all/0/1">Igor S. Savanov</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Raj_A/0/1/0/all/0/1">Ashish Raj</a> We present results obtained from the studies of magnetic activities on four solar-type stars (F-type star KIC 6791060, K-type star LO Peg, and two M-type planet-hosting stars K2-33 and EPIC 211901114) by using optical observations from several ground- and space-based telescopes. In this study, we investigate magnetic activities such as spot-topographic evolution and flaring events in these stars. We compare the results obtained from this study with that of the Sun. In the surface temperature maps, one active longitude hasRead More →

Demonstration of the broadband half-wave plate using the nine-layer sapphire for the CMB polarization experiment. (arXiv:1905.13520v1 [astro-ph.IM]) <a href="http://arxiv.org/find/astro-ph/1/au:+Komatsu_K/0/1/0/all/0/1">Kunimoto Komatsu</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Matsumura_T/0/1/0/all/0/1">Tomotake Matsumura</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Imada_H/0/1/0/all/0/1">Hiroaki Imada</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ishino_H/0/1/0/all/0/1">Hirokazu Ishino</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Katayama_N/0/1/0/all/0/1">Nobuhiko Katayama</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sakurai_Y/0/1/0/all/0/1">Yuki Sakurai</a> We report the development of the achromatic half-wave plate (AHWP) at millimeter wave for cosmic microwave background polarization experiments. We fabricate an AHWP consisting of nine a-cut sapphire plates based on the Pancharatnam recipe to cover a wide frequency range. The modulation efficiency and the phase are measured in a frequency range of 33 to 260 GHz with incident angles up to 10 degrees. We find the measurements at roomRead More →

Modeling observations of GRB 180720B: From radio to GeV gamma-rays. (arXiv:1905.13572v1 [astro-ph.HE]) <a href="http://arxiv.org/find/astro-ph/1/au:+Fraija_N/0/1/0/all/0/1">N. Fraija</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dichiara_S/0/1/0/all/0/1">S. Dichiara</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Pedreira_A/0/1/0/all/0/1">A.C. Caligula do E. S. Pedreira</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Galvan_Gamez_A/0/1/0/all/0/1">A. Galvan-Gamez</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Becerra_R/0/1/0/all/0/1">R. L. Becerra</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Montalvo_A/0/1/0/all/0/1">A. Montalvo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Montero_J/0/1/0/all/0/1">J. Montero</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kamenetskaia_B/0/1/0/all/0/1">B. Betancourt Kamenetskaia</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Zhang_B/0/1/0/all/0/1">B.B. Zhang</a> Early and late multiwavelength observations play an important role in determining the nature of the progenitor, circumburst medium, physical processes and emitting regions associated to the spectral and temporal features of bursts. GRB 180720B is a long and powerful burst detected by a large number of observatories in multiwavelenths that range from radio bands to GeV gamma-rays. The simultaneous multiwavelengthRead More →

Fast Solar Image Classification Using Deep Learning and its Importance for Automation in Solar Physics. (arXiv:1905.13575v1 [astro-ph.SR]) <a href="http://arxiv.org/find/astro-ph/1/au:+Armstrong_J/0/1/0/all/0/1">John A. Armstrong</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fletcher_L/0/1/0/all/0/1">Lyndsay Fletcher</a> The volume of data being collected in solar physics has exponentially increased over the past decade and with the introduction of the $textit{Daniel K. Inouye Solar Telescope}$ (DKIST) we will be entering the age of petabyte solar data. Automated feature detection will be an invaluable tool for post-processing of solar images to create catalogues of data ready for researchers to use. We propose a deep learning model to accomplish this; a deep convolutional neural network is adept at feature extraction andRead More →

Structure Formation with Two Periods of Inflation: Beyond PLaIn $Lambda$CDM. (arXiv:1905.13580v1 [astro-ph.CO]) <a href="http://arxiv.org/find/astro-ph/1/au:+Enqvist_K/0/1/0/all/0/1">Kari Enqvist</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sawala_T/0/1/0/all/0/1">Till Sawala</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Takahashi_T/0/1/0/all/0/1">Tomo Takahashi</a> We discuss structure formation in models with a spectator field in small-field inflation which accommodate a secondary period of inflation. In such models, subgalactic scale primordial fluctuations can be much suppressed in comparison to the usual power-law $Lambda$CDM model while the large scale fluctuations remain consistent with current observations. We discuss how a secondary inflationary epoch may give rise to observable features in the small scale power spectrum and hence be tested by the structures in the Local Universe. We discuss structure formation inRead More →

Critical Higgs Inflation and Second Order Gravitational Wave Signatures. (arXiv:1905.13581v1 [hep-ph]) <a href="http://arxiv.org/find/hep-ph/1/au:+Drees_M/0/1/0/all/0/1">Manuel Drees</a>, <a href="http://arxiv.org/find/hep-ph/1/au:+Xu_Y/0/1/0/all/0/1">Yong Xu</a> The self coupling $lambda$ of the Higgs boson in the Standard Model may show critical behavior, i.e. the Higgs potential may have a point at an energy scale $sim 10^{17-18}$ GeV where both the first and second derivatives (almost) vanish. Since $lambda$ is very small in this region, the Higgs boson can serve as inflaton even if its nonminimal coupling to the curvature scalar is only ${cal O}(10)$, thereby alleviating concerns about the perturbative unitarity of the theory. We find that just before the Higgs as inflaton entersRead More →

Distribution of red clump stars does not support the X-shaped Galactic bulge. (arXiv:1905.13592v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Lopez_Corredoira_M/0/1/0/all/0/1">M. Lopez-Corredoira</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lee_Y/0/1/0/all/0/1">Y.-W. Lee</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Garzon_F/0/1/0/all/0/1">F. Garzon</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lim_D/0/1/0/all/0/1">D. Lim</a> CONTEXT. Claims of an X-shaped Galactic bulge were based on the assumption of red clump stars as standard candles in some lines of sight crossing the off-plane bulge. However, some doubts have been cast on whether the two peaks in star counts along the line of sight really represent a double peak in the density distribution, or whether there is something wrong with the assumption of a unique constant absolute magnitude for all of these stars. AIMS. With theRead More →

Predicting Steady States of One-dimensional Collisionless Gravitating Systems. (arXiv:1905.13616v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Ragan_R/0/1/0/all/0/1">Robert J. Ragan</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Barnes_E/0/1/0/all/0/1">Eric I. Barnes</a> (University of Wisconsin-La Crosse) Building on the development of a Hermite-Legendre analysis of one-dimensional gravitating collisionless systems, we present a technique for determining the steady states of such systems. This provides an important component for understanding the physics involved in the relaxation of these kinds of systems. As the dark matter structures in the universe should have traits in common with these systems, insight into this relaxation can provide clues to larger astrophysical questions. For large perturbation strengths, we determine physically motivated parameter ranges for the simplestRead More →

Migration of D-type asteroids from the outer Solar System inferred from carbonate in meteorites. (arXiv:1905.13620v1 [astro-ph.EP]) <a href="http://arxiv.org/find/astro-ph/1/au:+Fujiya_W/0/1/0/all/0/1">Wataru Fujiya</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Hoppe_P/0/1/0/all/0/1">Peter Hoppe</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ushikubo_T/0/1/0/all/0/1">Takayuki Ushikubo</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Fukuda_K/0/1/0/all/0/1">Kohei Fukuda</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lindgren_P/0/1/0/all/0/1">Paula Lindgren</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lee_M/0/1/0/all/0/1">Martin R. Lee</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Koike_M/0/1/0/all/0/1">Mizuho Koike</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Shirai_K/0/1/0/all/0/1">Kotaro Shirai</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sano_Y/0/1/0/all/0/1">Yuji Sano</a> Recent dynamical models of Solar System evolution and isotope studies of rock-forming elements in meteorites have suggested that volatile-rich asteroids formed in the outer Solar System beyond Jupiter’s orbit, despite being currently located in the main asteroid belt. The ambient temperature under which asteroids formed is a crucial diagnostic to pinpoint the original location of asteroids and is potentially determined byRead More →

Relaxation of One-dimensional Collisionless Gravitating Systems. (arXiv:1905.13624v1 [astro-ph.GA]) <a href="http://arxiv.org/find/astro-ph/1/au:+Barnes_E/0/1/0/all/0/1">Eric I. Barnes</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ragan_R/0/1/0/all/0/1">Robert J. Ragan</a> (University of Wisconsin-La Crosse) In an effort to better understand collisionless relaxation processes in gravitational systems, we investigate one-dimensional models. Taking advantage of a Hermite-Legendre expansion of relevant distribution functions, we present analytical and numerical behaviors of Maxwell-Boltzmann entropy. In particular, we modestly perturb systems about a separable-solution equilibrium and observe their collisionless evolution to a steady state. We verify the time-independence of fine-grained entropy in these systems before turning our attention to the behavior of coarse-grained entropy. We also verify that there is no analogue to the collisionalRead More →