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We propose the use of wavelength-dependent spectroscopic absorption in the evanescent field of ultra-compact whispering gallery mode microspherical lasers as selective gas sensors and estimate few ppm detection sensitivity using a simple…

Instrumentation and Detectors · Physics 2018-07-10 Behsan Behzadi , Ravinder K. Jain , Mani Hossein-Zadeh

In the present paper, we consider the optical design of a zoom system for the active refocusing in laser guide star wavefront sensors. The system is designed according to the specifications coming from the Extremely Large Telescope…

Instrumentation and Methods for Astrophysics · Physics 2017-11-20 Eduard Muslimov , Kjetil Dohlen , Benoit Neichel , Emmanuel Hugot

The Transiting Exoplanet Survey Satellite (TESS) is the latest observational effort to find exoplanets and map bright transient optical phenomena. Supernovae (SN) are particularly interesting as cosmological standard candles for…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-26 B. W. Holwerda , S. Knabel , R. C. Steele , L. Strolger , J. Kielkopf , A. Jacques , W. Roemer

The gravitational microlensing technique allows the discovery of exoplanets around stars distributed in the disk of the galaxy towards the bulge. However, the alignment of two stars that led to the discovery is unique over the timescale of…

Earth and Planetary Astrophysics · Physics 2015-12-09 I. Boisse , A. Santerne , J. -P. Beaulieu , W. Fakhardji , N. C. Santos , P. Figueira , S. G. Sousa , C. Ranc

We report on femtosecond laser writing of single mode optical waveguides in chalcogenide Gallium Lanthanum Sulphide (GLS) glass. A multiscan fabrication process was employed to create waveguides with symmetric single mode guidance and low…

Filamentation of ultrashort laser pulses in the atmosphere offers unique opportunities for long-range transmission of high-power laser radiation and standoff detection. With the critical power of self-focusing scaling as the laser…

Stellar sources of gamma rays are one of the front lines in modern astrophysics whose understanding can benefit from observational tools not originally designed for their study. We take advantage of the high precision photometric…

High Energy Astrophysical Phenomena · Physics 2022-06-08 Enrique Mestre , Estrella Sánchez-Ayaso , Pedro L. Luque-Escamilla , Josep Martí , Josep M. Paredes , Daniel del Ser , Jorge Núñez

High precision spectroscopy on the $2 \ ^3 S \rightarrow 2 \ ^1 S$ transition is possible in ultracold optically trapped helium but the accuracy is limited by the ac-Stark shift induced by the optical dipole trap. To overcome this problem,…

Atomic Physics · Physics 2018-04-19 R. J. Rengelink , R. P. M. J. W. Notermans , W. Vassen

The 6.7~GHz methanol maser transition is exclusively associated with young, high-mass stars and represents a potential target for astrometric studies, including accurate determination of their distance through trigonometric parallax…

Astrophysics of Galaxies · Physics 2025-10-21 Lucas J. Hyland , Simon P. Ellingsen , Mark J. Reid

Imaging point sources with low angular separation near or below the Rayleigh criterion is important in astronomy, e.g., in the search for habitable exoplanets near stars. However, the measurement time required to resolve stars in the…

Optics · Physics 2021-07-07 Fanglin Bao , Hyunsoo Choi , Vaneet Aggarwal , Zubin Jacob

The identification of strong gravitational lenses in large surveys has historically been a rather time consuming exercise. Early data from the Herschel Astrophysical Terahertz Large Area Survey (Herschel-ATLAS) demonstrate that lenses can…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-22 Jo Short , Elizabeth Pearson , Peter Coles , Steve Eales

Lens time delays are a powerful probe of cosmology, provided that the gravitational potential of the main deflector can be modeled with sufficient precision. Recent work has shown that this can be achieved by detailed modeling of the host…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Xiao-Lei Meng , Tommaso Treu , Adriano Agnello , Matthew W. Auger , Kai Liao , Philip J. Marshall

An inversion technique has been developed to recover LTE one-dimensional model photospheres for late-type stars from very high resolution, high signal-to-noise stellar line profiles. It is successfully applied to the Sun by using a set of…

Astrophysics · Physics 2009-10-30 Carlos Allende Prieto , Basilio Ruiz Cobo , Ramon J. Garcia Lopez

We describe an experiment, located in south-east Colorado, USA, that measured aerosol optical depth profiles using two Lidar techniques. Two independent detectors measured scattered light from a vertical UV laser beam. One detector, located…

The development of a transportable microwave frequency standard based on the ground-state transition of $^{171}\mathrm{Yb^{+}}$ at ~12.6 GHz requires a compact laser system for cooling the ions, clearing out of long-lived states and also…

Habitable Worlds Observatory (HWO) presents a key challenge for technology development in the coming years, requiring a $>$ $100\times$ more stable system than \textit{JWST}. WaveDriver is a concept for a laser guide star spacecraft coupled…

We searched high resolution spectra of 5600 nearby stars for emission lines that are both inconsistent with a natural origin and unresolved spatially, as would be expected from extraterrestrial optical lasers. The spectra were obtained with…

Instrumentation and Methods for Astrophysics · Physics 2017-05-24 Nathaniel K. Tellis , Geoffrey W. Marcy

The development of sensitive large format imaging arrays for the infrared promises to provide revolutionary capabilities for space astronomy. For example, the Infrared Array Camera (IRAC) on SIRTF will use four 256 x 256 arrays to provide…

Astrophysics · Physics 2016-08-30 D. J. Fixsen , S. H. Moseley , R. G. Arendt

Adaptive optics (AO) systems are crucial for high-resolution astronomical observations by compensating for atmospheric turbulence. While laser guide stars (LGS) address high-order wavefront aberrations, natural guide stars (NGS) remain…

Instrumentation and Methods for Astrophysics · Physics 2024-10-17 Mojtaba Taheri , Mahdiyar Molahasani , Sam Ragland , Benoit Neichel , Peter Wizinowich

Star-galaxy classification is one of the most fundamental data-processing tasks in survey astronomy, and a critical starting point for the scientific exploitation of survey data. For bright sources this classification can be done with…

Instrumentation and Methods for Astrophysics · Physics 2013-07-30 Marc Henrion , Daniel J. Mortlock , David J. Hand , Axel Gandy
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