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Our motion through the Universe generates a dipole in the temperature anisotropies of the Cosmic Microwave Background (CMB) and also in the angular distribution of sources. If the cosmological principle is valid, these two dipoles are…

宇宙学与河外天体物理 · 物理学 2023-06-09 Charles Dalang , Camille Bonvin

The cosmological principle states that our Universe is statistically homogeneous and isotropic at large scales. However, due to the relative motion of the Solar System, an additional kinematic dipole can be detected in the distribution of…

宇宙学与河外天体物理 · 物理学 2022-08-31 Yu-Tian Xu , Ji-Ping Dai , Dong Zhao , Jun-Qing Xia

We report unidirectional radiation of a magnetic dipole above planar metal surface, the radiation direction can be manipulated via changing the distance between the dipole and the surface. This phenomenon is unique for the combination of…

光学 · 物理学 2015-06-16 Zheng Xi , Yonghua Lu , Peijun Yao , Wenhai Yu , Pei Wang , Hai Ming

The beaming effect (aka Doppler boosting) induces a variation in the observed flux of a luminous object, following its observed radial velocity variation. We describe a photometric signal induced by the beaming effect during eclipse of…

太阳与恒星天体物理 · 物理学 2015-05-28 Avi Shporer , Tim Brown , Tsevi Mazeh , Shay Zucker

We predict the polarization of cosmic microwave background (CMB) photons that results from a cosmic bubble collision. The polarization is purely E-mode, symmetric around the axis pointing towards the collision bubble, and has several…

宇宙学与河外天体物理 · 物理学 2015-05-19 Bartlomiej Czech , Matthew Kleban , Klaus Larjo , Thomas S. Levi , Kris Sigurdson

During a solar magnetic field reversal the magnetic dipole moment does not vanish, but migrates between poles, in contradiction to the predictions of mean-field dynamo theory. We try to explain this as a consequence of magnetic…

太阳与恒星天体物理 · 物理学 2015-06-12 David Moss , Leonid L. Kitchatinov , Dmitri Sokoloff

Some active stars show a so-called flip-flop phenomenon in which the main spot activity periodically switches between two active longitudes that are 180 degrees apart. In this paper we study the flip-flop phenomenon by converting results…

天体物理学 · 物理学 2009-11-11 H. Korhonen , D. Elstner

Parity violation in the cosmic microwave background (CMB) radiation has been confirmed by recent Planck observation. In this paper, we extend our previous work [P. Naselsky et al. Astrophys. J. {\bf 749}, 31 (2012)] on the directional…

宇宙学与河外天体物理 · 物理学 2017-02-16 Wen Zhao

We consider a dynamo wave in the solar convective shell for the kinematic $\alpha\omega$-dynamo model. The spectrum and eigenfunctions of the corresponding equations are derived analytically with the aid of the WKB method. Our main aim here…

天体物理学 · 物理学 2009-11-06 Victor Galitski , D. D. Sokoloff

Many observations in recent times have shown evidence against the standard assumption of isotropy in the Big Bang model. Introducing a superhorizon scalar metric perturbation has been able to explain some of these anomalies. In this work,…

宇宙学与河外天体物理 · 物理学 2021-07-21 Kaustav K. Das , Kishan Sankharva , Pankaj Jain

According to the cosmological principle, the Universe should appear isotropic, without any preferred directions, to an observer whom we may consider to be fixed in the co-moving co-ordinate system of the expanding Universe. Such an observer…

宇宙学与河外天体物理 · 物理学 2013-06-11 Ashok K. Singal

Several statistical anomalies in the CMB temperature anisotropies seem to defy the assumption of a homogeneous and isotropic universe. In particular, a dipole modulation has been detected both in WMAP and Planck data. We adapt the…

宇宙学与河外天体物理 · 物理学 2014-07-29 R. Fernández-Cobos , P. Vielva , D. Pietrobon , A. Balbi , E. Martínez-González , R. B. Barreiro

We present a determination of the cosmic microwave background dipole amplitude and direction from the COBE Differential Microwave Radiometers (DMR) first year of data. Data from the six DMR channels are consistent with a Doppler-shifted…

天体物理学 · 物理学 2009-10-22 A. Kogut , C. Lineweaver , G. F. Smoot , C. L. Bennett , A. Banday

Our motion relative to the cosmic-microwave-background (CMB) rest frame deflects light rays giving rise to shifts as large as L -> L(1+beta), where beta=0.00123 is our velocity (in units of the speed of light) on measurements CMB…

宇宙学与河外天体物理 · 物理学 2014-01-22 Donghui Jeong , Jens Chluba , Liang Dai , Marc Kamionkowski , Xin Wang

We address the problem of map-making with data from the Planck Surveyor High Frequency Instrument, with an emphasis on the understanding and modelling of instrumental effects, and in particular that of sidelobe straylight. We propose a…

天体物理学 · 物理学 2007-05-23 J. Delabrouille , R. Gispert , J. -L. Puget

The channel-to-channel migration of radio interferometric baselines for the same antenna separation causes a flat spectrum source that should have remained in the zeroth delay (line-of-sight) mode to become centered around a higher mode -…

天体物理仪器与方法 · 物理学 2018-10-16 Magendran S

The proper motion (also known as position drift) field of extragalactic sources at cosmological distances across our sky can be used to measure the acceleration of the Solar System through the aberration effect. If measured very precisely,…

宇宙学与河外天体物理 · 物理学 2025-08-06 Andreas Tsigkas Kouvelis , Asta Heinesen , Shashank Shalgar , Mikołaj Korzyński

There is tentative evidence for a mismatch between the rest frames of matter and the cosmic microwave background, the "quasar dipole anomaly". We consider such a dipole in tilted anisotropic models, for a range of scenarios and sources:…

宇宙学与河外天体物理 · 物理学 2025-12-04 Alicia Martín , Constantinos Skordis , Deaglan J. Bartlett , Harry Desmond , Pedro G. Ferreira , Tariq Yasin

We provide a new derivation of the anisotropies of the cosmic microwave background (CMB), and find an exact expression that can be readily expanded perturbatively. Close attention is paid to gauge issues, with the motivation to examine the…

天体物理学 · 物理学 2009-01-08 J. P. Zibin , Douglas Scott

The recoil optical force and torque acting on an electromagnetic dipole are typically derived by computing the imbalance in radiated linear and angular electromagnetic momentum coming from the source, using Maxwell stress tensor…