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Related papers: On the spin-temperature evolution during the epoch…

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The redshifted 21-cm line of distant neutral H atoms provides a probe of the cosmic ``dark ages'' and the epoch of reionization (``EOR'') which ended them. The radio continuum produced by this redshifted line can be seen in absorption or…

Astrophysics · Physics 2009-11-13 Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen , Hugh Merz

The spin transition in LaCoO3 is investigated by temperature-dependent resonant soft X-ray emission spectroscopy near the Co 2p absorption edges. This element-specific technique is more bulk sensitive with respect to the temperature induced…

Strongly Correlated Electrons · Physics 2011-12-30 M. Magnuson , S. M. Butorin , C. Såthe , J. Nordgren , P. Ravindran

The quantum dynamics of a two-level system coupled to an Ohmic spin- bath is studied by means of the perturbation approach based on a unitary transformation. A scattering function $\xi_k$ is introduced in the transformation to take into…

Quantum Physics · Physics 2015-05-27 Zhiguo Lü , H. Zheng

Heating of neutral gas by energetic sources is crucial for the prediction of the 21 cm signal during the epoch of reionization (EoR). To investigate differences induced on statistics of the 21 cm signal by various source types, we use five…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-26 Qing-Bo Ma , Benedetta Ciardi , Marius B. Eide , Philipp Busch , Yi Mao , Qi-Jun Zhi

We present an analytic formulation to model the fluctuating component of the HI signal from the epoch of reionization during the phase of partial heating. During this phase, we assume self-ionized regions, whose size distribution can be…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-14 Janakee Raste , Shiv Sethi

We investigate the interaction of Lyman alpha photons produced by the first stars in the universe with the intergalactic medium (IGM) prior to reionization. The background Lyman alpha spectral profile is obtained by solving a Fokker-Planck…

Astrophysics · Physics 2009-11-07 Xuelei Chen , Jordi Miralda-Escude

Spin-polarized scanning tunneling microscopy investigations reveal a significant increase of the magnetic period of spin spirals in three-atomic-layer-thick Fe films on Ir(111), from about 4nm at 8K to about 65nm at room temperature. We…

Mesoscale and Nanoscale Physics · Physics 2017-07-26 Aurore Finco , Levente Rózsa , Pin-Jui Hsu , André Kubetzka , Elena Vedmedenko , Kirsten von Bergmann , Roland Wiesendanger

We present here predictions for the spatial distribution of 21 cm brightness temperature fluctuations from high-dynamic-range simulations for AGN-dominated reionization histories that have been tested against available Lyman-alpha and CMB…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-17 Girish Kulkarni , Tirthankar Roy Choudhury , Ewald Puchwein , Martin G. Haehnelt

The time evolution of a spin-1/2 particle under the influence of a locally applied external magnetic field, and interacting with anisotropic spin environment in thermal equilibrium at temperature $T$ is studied. The exact analytical form of…

Quantum Physics · Physics 2011-10-19 Y. Hamdouni , F. Petruccione

Patchy reionization leaves a number of imprints on the small-scale cosmic microwave background (CMB) temperature fluctuations, the largest of which is the kinematic Sunyaev-Zel'dovich (kSZ), the Doppler shift of CMB photons scattering off…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-26 Simone Ferraro , Kendrick M. Smith

We propose a deep learning analyzing technique with convolutional neural network (CNN) to predict the evolutionary track of the Epoch of Reionization (EoR) from the 21-cm differential brightness temperature tomography images. We use…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Yungi Kwon , Sungwook E. Hong , Inkyu Park

We study contributions from inhomogeneous (patchy) reionization to arcminute scale ($1000 < \ell < 10,000$) cosmic microwave background (CMB) anisotropies. We show that inhomogeneities in the ionization fraction, rather than in the mean…

Astrophysics · Physics 2008-11-26 M. G. Santos , A. Cooray , Z. Haiman , L. Knox , C. -P. Ma

The process of reionization is now believed to have proceeded in an orchestrated manner beginning with UV photons emitted by high redshift galaxies containing a large fraction of Population III stars carving out ionised regions around them.…

Astrophysics · Physics 2008-11-26 Anze Slosar , Asantha Cooray , Joseph Silk

We present an analytic formalism to compute the fluctuating component of the \ion{H}{1} signal and extend it to take into account the effects of partial Lyman-$\alpha$ coupling during the era of cosmic dawn. We use excursion set formalism…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-15 Janakee Raste , Shiv Sethi

We study the constraints that future multifrequency Cosmic Microwave Background (CMB) experiments will be able to set on the metal enrichment history of the Inter Galactic Medium at the epoch of reionisation. We forecast the signal to noise…

Astrophysics · Physics 2008-11-26 Carlos Hernandez-Monteagudo , Licia Verde , Raul Jimenez

We studied the magnetic properties, in particular dynamics, of the correlated spins associated with natural defects in the organic spin chain compounds ($o$-DMTTF)$_2X$ ($X$ = Br, Cl) by means of electron spin resonance (ESR) spectroscopy.…

Strongly Correlated Electrons · Physics 2019-12-18 J. Zeisner , O. Pilone , L. Soriano , G. Gerbaud , H. Vezin , O. Jeannin , M. Fourmigué , B. Büchner , V. Kataev , S. Bertaina

Since the discovery of the giant magnetoresistance (GMR) effect the use of the intrinsic angular momentum of the electrons has opened up new spin based device concepts. The two channel model of spin-up and spin-down electrons with…

Mesoscale and Nanoscale Physics · Physics 2014-12-24 F. K. Dejene , J. Flipse , G. E. W. Bauer , B. J. van Wees

Models and simulations of the epoch of reionization predict that spectra of the 21-cm transition of atomic hydrogen will show a clear fluctuation peak, at a redshift and scale, respectively, that mark the central stage of reionization and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Anastasia Fialkov , Rennan Barkana , Eli Visbal

The thermal evolution of neutron stars is coupled to their spin down and the resulting changes in structure and chemical composition. This coupling correlates stellar surface temperatures with rotational state as well as time. We report an…

Astrophysics · Physics 2009-06-23 Morten Stejner , Fridolin Weber , Jes Madsen

On large angular scales, CMB polarization depends mostly on the evolution of the ionization level of the IGM during reionization. In order to avoid biasing parameter estimates, an accurate and model independent approach to reionization is…

Astrophysics · Physics 2009-06-23 Loris P. L. Colombo , Elena Pierpaoli