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相关论文: On a spectral pattern of the Von-Neumann probes

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In this paper we consider efficiency of self-reproducing extraterrestrial Von-Neumann micro scale robots and analyse the observational characteristics. By examining the natural scenario of moving in the HII clouds, it has been found that…

科普物理 · 物理学 2020-05-13 Z. Osmanov

In the present paper we consider the Type-2.x and Type-3.x extraterrestrial von-Neumann probes and study the problem of their detectability by the world's largest radio telescope: the Five-hundred-meter Aperture Spherical Radio Telescope…

科普物理 · 物理学 2021-10-05 Zaza Osmanov

We present a comprehensive and sensitive unbiased survey of interstellar features in the near-UV range (3050-3700 {\AA}). We combined a large number of VLT/UVES archival observations of a sample of highly reddened early type stars --…

星系天体物理 · 物理学 2015-08-06 Neil Hemant Bhatt , Jan Cami

In this paper we present Spitzer Infrared Spectrograph spectroscopy for 14 intermediate-mass young stellar objects. We use Spitzer spectroscopy to investigate the physical properties of these sources and their environments. Our sample can…

太阳与恒星天体物理 · 物理学 2015-05-30 Jan Pitann , Martin Hennemann , Stephan Birkmann , Jeroen Bouwman , Oliver Krause , Thomas Henning

The ongoing quest to identify molecules in the interstellar medium by their electronic spectra in the visible region is reviewed. Identification of molecular absorption is described in the context of the elucidation of the carriers of the…

天体物理学 · 物理学 2011-03-10 T. W. Schmidt , R. G. Sharp

X-ray emission is a common feature of all varieties of isolated neutron stars (INS) and, thanks to the advent of sensitive instruments with good spectroscopic, timing, and imaging capabilities, X-ray observations have become an essential…

高能天体物理现象 · 物理学 2015-05-19 Sandro Mereghetti

The spectral properties of type Ia supernovae in the ultraviolet (UV) are investigated using the early-time spectra of SN 2001ep and SN 2001eh obtained using the Hubble Space Telescope (HST). A series of spectral models is computed with a…

Most cosmic ray antiprotons observed near the Earth are secondaries produced in collisions of energetic cosmic ray (CR) particles with interstellar gas. The spectrum of secondary antiprotons is expected to peak at ~2 GeV and decrease…

天体物理学 · 物理学 2007-05-23 I. V. Moskalenko , E. R. Christian , A. A. Moiseev , J. F. Ormes , A. W. Strong

While the members of the Type IIn category of supernovae are united by the presence of strong multicomponent Balmer emission lines in their spectra, they are quite heterogeneous with respect to other properties such as Balmer line profiles,…

天体物理学 · 物理学 2009-06-23 Jennifer L. Hoffman

We demonstrate a new scheme of infrared spectroscopy with visible light sources and detectors. The technique relies on the nonlinear interference of correlated photons, produced via spontaneous parametric down conversion in a nonlinear…

Interstellar antiproton fluxes can arise from dark matter annihilating or decaying into quarks or gluons that subsequently fragment into antiprotons. Evaporation of primordial black holes also can produce a significant antiproton cosmic-ray…

高能物理 - 唯象学 · 物理学 2009-10-31 James D. Wells , Alexander Moiseev , Jonathan F. Ormes

By applying quantum chemical calculation, interstellar infrared spectrum was categorized to three classes. Type-A show unusual feature of strong peaks at 11.3,12.9, and 14.0 micrometer. Usually observed 6.2, 7.7, and 8.6 micrometer bands…

星系天体物理 · 物理学 2017-08-29 Norio Ota

The recently discovered fast radio bursts (FRBs), presumably of extra-galactic origin, have the potential to become a powerful probe of the intergalactic medium (IGM). We point out a few such potential applications. We provide expressions…

高能天体物理现象 · 物理学 2015-12-29 Z. Zheng , E. O. Ofek , S. R. Kulkarni , J. D. Neill , M. Juric

We present medium-resolution (R~700) near-infrared (lambda = 1 - 2.5 micron) spectra of a sample of planetary nebulae (PNe). A narrow slit was used which sampled discrete locations within the nebulae; observations were obtained at one or…

天体物理学 · 物理学 2009-10-31 Joseph L. Hora , William B. Latter , Lynne K. Deutsch

I present an overview of optical observations (mostly spectra) of Type II supernovae. SNe II are defined by the presence of hydrogen, and exhibit a very wide variety of properties. SNe II-L tend to show evidence of late-time interaction…

天体物理学 · 物理学 2009-10-31 A. V. Filippenko

In the cm-wavelength range, an extraterrestrial electromagnetic narrow band (sine wave) beacon is an excellent choice to get alien attention across interstellar distances because 1) it is not strongly affected by interstellar /…

天体物理仪器与方法 · 物理学 2018-05-08 G. R. Harp , R. F. Ackermann , Samantha K. Blair , J. Arbunich , P. R. Backus , J. C. Tarter , the ATA Team

Anomalous X-ray pulsars, compact non-pulsing X-ray sources in supernova remnants, and X-ray bursters are three distinct types of sources for which there are viable models that attribute their X-ray emission to thermal emission from the…

天体物理学 · 物理学 2009-10-31 Dimitrios Psaltis , Feryal Ozel , Simon DeDeo

Characterization of exoplanets has matured in recent years, particularly through studies of exoplanetary atmospheres of transiting planets at infra-red wavelenegths. The primary source for such observations has been the Spitzer Space…

地球与行星天体物理 · 物理学 2015-05-30 Stephen R. Kane , Dawn M. Gelino

It is shown that high-energy astrophysical neutrinos observed in the IceCube experiment can be produced by protons accelerated in extragalactic Type IIn supernova remnants by shocks propagating in the dense circumstellar medium. The…

高能天体物理现象 · 物理学 2016-03-16 V. N. Zirakashvili , V. S. Ptuskin

High-resolution ultraviolet spectra from the Space Telescope Imaging Spectrograph (STIS) were used to search for unidentified interstellar absorption features in the well studied sightline towards X Per (HD 24534). The significance of…

星系天体物理 · 物理学 2009-08-24 Joshua D. Destree , Theodore P. Snow
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