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Related papers: Polarised radio pulsations from a new T dwarf bina…

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We present a sequence of high resolution (R~20,000 or 15 km/s) infrared spectra of stars and brown dwarfs spanning spectral types M2.5 to T6. Observations of 16 objects were obtained using eight echelle orders to cover part of the J-band…

We present the discovery of seven ultracool brown dwarfs identified with the Wide-field Infrared Survey Explorer (WISE). Near-infrared spectroscopy reveals deep absorption bands of H_2O and CH_4 that indicate all seven of the brown dwarfs…

The pulsed radio emission of rotating neutron stars is connected to slow resistive instabilities feeding off an inhomogeneous twist profile within the open circuit. This paper considers the stability of a weakly sheared, quantizing magnetic…

High Energy Astrophysical Phenomena · Physics 2022-07-27 Christopher Thompson

Aims: We aimed to monitor the optical linear polarimetric signal of the magnetized, rapidly rotating M8.5 dwarf TVLM 513$-$46546. Methods: $R$- and $I$-band linear polarimetry images were collected with the ALFOSC instrument of the 2.56-m…

Solar and Stellar Astrophysics · Physics 2015-08-19 P. A. Miles-Páez , M. R. Zapatero Osorio , E. Pallé

The Deeper, Wider, Faster (DWF) program coordinates observations with telescopes across the electromagnetic spectrum, searching for transients on timescales of milliseconds to days. The tenth DWF observing run was carried out in near…

Observations of radio emission in about 10 per cent of ultra-cool dwarfs (UCDs) indicate the presence of strong, persistent magnetic fields in these stars. These results are in contrast to early theoretical expectations on fully-convective…

Solar and Stellar Astrophysics · Physics 2018-11-26 Andrew Zic , Christene Lynch , Tara Murphy , David L. Kaplan , Poonam Chandra

Gravitational waves (GWs) can resonate with magnetic fields through the Gertsenshtein-Zeldovich effect, producing electromagnetic signals at the same frequency. In pulsar magnetospheres, this conversion may yield a faint radio-band signal…

General Relativity and Quantum Cosmology · Physics 2026-05-22 Wei Hong , Peng He , Tong-Jie Zhang , Shi-Yu Li , Pei Wang

Recently, a number of ultracool dwarfs have been found to produce periodic radio bursts with high brightness temperature and polarization degree; the emission properties are similar to the auroral radio emissions of the magnetized planets…

Solar and Stellar Astrophysics · Physics 2015-06-03 A. A. Kuznetsov , J. G. Doyle , S. Yu , G. Hallinan , A. Antonova , A. Golden

We report on radio observations of four magnetars SGR 0501+4516, Swift 1834.9-0846, 1E 1841-045, SGR 1900+14 and a magnetar-like pulsar PSR J1846-0258 with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) at 1250 MHz.…

High Energy Astrophysical Phenomena · Physics 2024-12-31 Juntao Bai , Na Wang , Shi Dai , Shuangqiang Wang , Jianping Yuan , Wenming Yan , Lunhua Shang , Xin Xu , Shijun Dang , Zhen Zhang

We present two epochs of MPG/ESO 2.2m GROND simultaneous 6-band ($r'i'z'JHK$) photometric monitoring of the closest known L/T transition brown dwarf binary WISE J104915.57-531906.1AB. We report here the first resolved variability monitoring…

We present new spectroscopy and astrometry to characterize the nearby brown dwarf WISEP J180026.60+013453.1. The optical spectral type, L7.5, is in agreement with the previously reported near-infrared spectral type. The preliminary…

Solar and Stellar Astrophysics · Physics 2015-09-16 John E. Gizis , Adam J. Burgasser , Frederick J. Vrba

Radio detections of stellar systems provide a window onto stellar magnetic activity and the space weather conditions of extrasolar planets, information that is difficult to attain at other wavelengths. There have been recent advances…

We present the timing parameters of nine pulsars discovered in a survey of intermediate Galactic latitudes at 1400 MHz with the Parkes radio telescope. Eight of these pulsars possess small pulse periods and period derivatives thought to be…

Astrophysics · Physics 2009-11-06 R. T. Edwards , M. Bailes

Recent studies have shown possible connections between highly magnetized neutron stars ("magnetars"), whose X-ray emission is too bright to be powered by rotational energy, and ordinary radio pulsars. In addition to the magnetar SGR…

High Energy Astrophysical Phenomena · Physics 2017-04-12 J. Dexter , N. Degenaar , M. Kerr , A. Deller , J. Deneva , P. Lazarus , M. Kramer , D. Champion , R. Karuppusamy

Coherent radio emission with properties similar to planetary auroral signals has been reported from GJ 1151, a quiescent, slow-rotating mid-M star, by the LOFAR Two-metre (120-170 MHz) Sky Survey (LoTSS). The observed {LOFAR} emission is…

We report on the discovery of PSR J1141-6545, a radio pulsar in an eccentric, relativistic 5-hr binary orbit. The pulsar shows no evidence for being recycled, having pulse period P = 394 ms, characteristic age tau_c = 1.4 x 10^6 yr, and…

We consider the magnetic interaction of exoplanets orbiting M-dwarfs, calculating the expected Poynting flux carried upstream along Alfv\'{e}n wings to the central star. A region of emission analogous to the Io footprint observed in…

Earth and Planetary Astrophysics · Physics 2018-02-28 S. Turnpenney , J. D. Nichols , G. A. Wynn , M. R. Burleigh

JWST is opening many avenues for exploration. For cold brown dwarfs and exoplanets, JWST has opened the door to the mid-infrared wavelength region, where such objects emit significant energy. For the first time, astronomers have access to…

Solar and Stellar Astrophysics · Physics 2025-01-07 S. K. Leggett , Pascal Tremblin

We present the detection of 68 sources from the most sensitive radio survey in circular polarisation conducted to date. We use the second data release of the 144 MHz LOFAR Two-metre Sky Survey to produce circularly-polarised maps with…