English
Related papers

Related papers: A Search for Optical Laser Emission from Alpha Cen…

200 papers

The recent discovery of an earth-like planet around Proxima Centauri has drawn much attention to this star and its environment. We performed a series of observations of Proxima Centauri using SPHERE, the planet finder instrument installed…

A laser diffraction experiment was conducted to study light propagation in air. The experiment is easy to reproduce and it is based on simple optical principles. Two optical sensors (segmented photo-diodes) are used for measuring the…

Astrophysics · Physics 2007-05-23 C. E. Navia , C. R. A. Augusto , D. F. Franceschini , M. B. Robba , K. H. Tsui

We present new analyses of ALMA 12-m and ACA observations at 233 GHz (1.3 mm) of the Proxima Centauri system with sensitivities of 9.5 and 47 $\mu$Jy beam$^{-1}$, respectively, taken from 2017 January 21 through 2017 April 25. These…

Earth and Planetary Astrophysics · Physics 2018-03-14 Meredith A. MacGregor , Alycia J. Weinberger , David J. Wilner , Adam F. Kowalski , Steven R. Cranmer

A posteriori anisotropy study of ultra-high energy cosmic rays (UHECRs) with the Pierre Auger Observatory (PAO) has shown evidence of excess of cosmic ray particles above 55 EeV within $18^{\circ}$ of the direction of the radio galaxy…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Ruo-Yu Liu , Xiang-Yu Wang , Wei Wang , A. M. Taylor

The precise mechanisms that provide the non-radiative energy for heating the chromosphere and the corona of the Sun and those of other stars constitute an active field of research. By studying stellar chromospheres one aims at identifying…

The nearby radio galaxy Centaurus A is poorly studied at high frequencies with conventional radio telescopes because of its very large angular size, but is one of a very few extragalactic objects to be detected and resolved by the Wilkinson…

Astrophysics · Physics 2009-11-13 M. J. Hardcastle , C. C. Cheung , I. J. Feain , L. Stawarz

At a distance of about 3.8 Mpc, the radio galaxy Centaurus A is the closest active galaxy. Therefore it is a key target for studying the innermost regions of active galactic nuclei (AGN). VLBI observations conducted within the framework of…

Astrophysics of Galaxies · Physics 2010-07-27 Cornelia Müller , M. Kadler , R. Ojha , M. Böck , C. M. Fromm , E. Ros , R. E. Rothschild , J. Wilms , TANAMI team

We have studied the X-ray point source population of Centaurus A (NGC 5128) using data from four archival CHANDRA observations. We detected 272 point-like X-ray sources within a radius of 10 arcmin from the centre. Approximately half of…

Astrophysics · Physics 2009-11-11 R. Voss , M. Gilfanov

For more than a decade, Alpha Centauri AB (G2V+K1V) has been observed by Chandra, in a long-term program to follow coronal (T~1MK) activity cycles of the two sunlike stars. Over 2008.4-2017.8, nineteen HRC-I exposures were taken, each about…

Solar and Stellar Astrophysics · Physics 2018-11-28 Thomas R. Ayres

We present results from the most comprehensive radio monitoring campaign towards the closest star to our Sun, Proxima Centauri. We report 1.1 to 3.1 GHz observations with the Australian Telescope Compact Array over 18 consecutive days in…

We report preliminary results from an arcsecond-resolution X-ray survey of nearby galaxies using ACIS on board Chandra. The total sample consists of 41 low-luminosity AGNs, including Seyferts, LINERs, and LINER/H II transition objects. In…

Results from exoplanet surveys indicate that small planets (super-Earth size and below) are abundant in our Galaxy. However, little is known about their interiors and atmospheres. There is therefore a need to find small planets transiting…

On the Large Phased Array (LPA) of Lebedev Physics Institute (LPI), a search for pulsars outside the Galaxy plane was carried out in a 300 sq. deg area. The search with a sensitivity 5-10 times better than that of previously conducted…

High Energy Astrophysical Phenomena · Physics 2023-05-03 S. A. Tyul'bashev , G. E. Tyul'basheva

The Alpha Centauri AB system is an attractive one for radial velocity observations to detect potential exoplanets. The high metallicity of both Alpha Centauri A and B suggest that they could have possessed circumstellar discs capable of…

Earth and Planetary Astrophysics · Physics 2015-06-04 Duncan Forgan

We search for narrow-line optical emission from dark matter decay by stacking dark-sky spectra from the Dark Energy Spectroscopic Instrument (DESI) at the redshift of nearby galaxies from DESI's Bright Galaxy and Luminous Red Galaxy…

An observation of the gravitationally lensed system 2016+112 with the Chandra X-ray Observatory has resolved a mystery regarding the proposed presence of a dark matter object in the lens plane of this system. The Chandra ACIS observation…

Astrophysics · Physics 2009-11-06 G. Chartas , M. Bautz , G. Garmire , C. Jones , D. P. Schneider

We present a search for [CII] line and dust continuum emission from optical dropout galaxies at $z>6$ using ASPECS, our ALMA Spectroscopic Survey in the Hubble Ultra-Deep Field (UDF). Our observations, which cover the frequency range…

We summarize results of a search for X-ray-emitting binary stars in the massive globular cluster Omega Centauri (NGC 5139) using Chandra and HST. ACIS-I imaging reveals 180 X-ray sources, of which we estimate that 45-70 are associated with…

Astrophysics of Galaxies · Physics 2015-05-20 Daryl Haggard , Adrienne M. Cool , Tersi Arias , Michelle B. Brochmann , Jay Anderson , Melvyn B. Davies

This work is part of an ongoing project which aims to detect terrestrial planets in our neighbouring star system $\alpha$ Centauri using the Doppler method. Owing to the small angular separation between the two components of the $\alpha$…

Earth and Planetary Astrophysics · Physics 2014-12-22 Christoph Bergmann , Michael Endl , John B. Hearnshaw , Robert A. Wittenmyer , Duncan J. Wright

Deep HST-WFPC2 observations of the stellar population in the globular cluster Omega Cen (NGC 5139) have been used to measure the luminosity function of main sequence stars at the low-mass end. Two fields have been investigated, located…

Astrophysics · Physics 2009-10-31 Guido De Marchi