Opto-mechanical effects in self-organization of a Bose-Einstein condensate in an optical cavity

The influence of mirror motion on the spatial self organization of a Bose-Einstein condensate (BEC) in an optical cavity is studied. We show that the mirror dynamics tends to destroy the process of self organization. An additional external phonon pump is shown to modify the critical photon pump needed to observe the onset of self organization.Comment: 10 pages, 10 figure

Cluster decay half lives of trans-lead nuclei within the Coulomb and proximity potential model

Within the Coulomb and proximity potential model (CPPM) the cluster decay process in {199-226}^Fr, {206-232}^Ac, {209-237}^Th, {212-238}^Pa, {217-241}^U, {225-242}^Np, {225-244}^Pu, {231-246}^Am, {202-230}^Ra and {233-249}^Cm isotopes leading to the doubly magic 208^Pb and neighbouring nuclei are studied. The computed half lives are compared with available experimental data and are in good agreement with each other. The half lives are also computed using the Universal formula for cluster decay (UNIV) of Poenaru et al, Universal decay law (UDL) and the scaling law of Horoi et al, and their comparisons with CPPM values are found to be in agreement. The calculations for the emission of 22^O, 20^O, 20^O from the parents {209-237}^Th, {202-230}^Ra and {217-240}^U respectively were the experimental values are not available are also done. It is found that most of the decay modes are favourable for measurement, and this observation will serve as a guide to the future experiments. The odd-even staggering (OES) are found to be more prominent in the emission of odd mass clusters. The Geiger - Nuttall plots of log_10(T_1/2) vs. Q^{-1/2} for various clusters ranging from 14^C to 34^Si from different isotopes of heavy parent nuclei with atomic numbers within the range 87 \leq Z \leq 96 have been studied and are found to be linear. Our study reveals the role of doubly magic 208^Pb daughter nuclei in cluster decay process and also reveal the fact that the role of neutron shell closure is crucial than proton shell closure.Comment: 39 pages, 8 figure

Probing the circumgalactic baryons through cross-correlations

We study the cross-correlation of distribution of galaxies, the Sunyaev-Zel'dovich (SZ) and X-ray power spectra of galaxies from current and upcoming surveys and show these to be excellent probes of the nature, i.e. extent, evolution and energetics, of the circumgalactic medium (CGM). The SZ-galaxy cross-power spectrum, especially at large multipoles, depends on the steepness of the pressure profile of the CGM. This property of the SZ signal can, thus, be used to constrain the pressure profile of the CGM. The X-ray cross power spectrum also has a similar shape. However, it is much more sensitive to the underlying density profile. We forecast the detectability of the cross-correlated galaxy distribution, SZ and X-ray signals by combining South Pole Telescope-Dark Energy Survey (SPT-DES) and eROSITA-DES/eROSITA-LSST (extended ROentgen Survey with an Imaging Telescope Array-Large Synoptic Survey Telescope) surveys, respectively. We find that, for the SPT-DES survey, the signal-to-noise ratio (SNR) peaks at high mass and redshift with SNR $\sim 9$ around $M_h\sim 10^{13} h^{-1} M_{\odot}$ and $z\sim 1.5\hbox{--} 2$ for flat density and temperature profiles. The SNR peaks at $\sim 6 (12 )$ for the eROSITA-DES (eROSITA-LSST) surveys. We also perform a Fisher matrix analysis to find the constraint on the gas fraction in the CGM in the presence or absence of an unknown redshift evolution of the gas fraction. Finally, we demonstrate that the cross-correlated SZ-galaxy and X-ray-galaxy power spectrum can be used as powerful probes of the CGM energetics and potentially discriminate between different feedback models recently proposed in the literature; for example, one can distinguish a `no active galactic nuclei feedback' scenario from a CGM energized by `fixed-velocity hot winds' at greater than $3\sigma$.Comment: 14 pages, 10 figures, 4 tables, accepted for publication in MNRA

A Landau fluid model for warm collisionless plasmas

A Landau fluid model for a collisionless electron-proton magnetized plasma, that accurately reproduces the dispersion relation and the Landau damping rate of all the magnetohydrodynamic waves, is presented. It is obtained by an accurate closure of the hydrodynamic hierarchy at the level of the fourth order moments, based on linear kinetic theory. It retains non-gyrotropic corrections to the pressure and heat flux tensors up to the second order in the ratio between the considered frequencies and the ion cyclotron frequency.Comment: to appear in Phys. Plasma

Sleepy Berekspresi Lewat Graffiti

Graffiti merupakan seni visual jalanan yang mengutamakan permainan tulisan, di mana huruf dan kata menjadi obyek utama dalam penciptaannya. SLEEPY adalah kata yang merepresentasikan penulis dalam menciptakan karya graffiti. Bermula dari keinginan penulis mengangkat graffiti sebagai karya seni lukis, yang mendorong penulis mengangkat graffiti dalam penciptaan karya tugas akhir. Penciptaan karya SLEEPY meliputi lima karya dengan konsep yang berbeda-beda, namun terdapat keterkaitan antar kelima konsep tersebut yaitu unsur warna. Warna yang digunakan dalam penciptaan karya menggunakan warna-warna yang bersifat kuat dan cerah. Terdapat dua media yang digunakan yaitu tembok dan mobil. Proses penciptaan tersebut menggunakan teknik semprot dengan cat semprot atau aerosol spray paint. SLEEPY tercipta dari ungkapan penulis sehari-hari yang sederhana namun mewakili ekspresi terdalam penulis menuju kebahagiaan. Dengan permainan warna yang cerah penulis mempunyai harapan karya graffiti SLEEPY dapat menghibur mata pengguna jalan yang sedang penat oleh kepadatan kota. Kata Kunci : SLEEPY, ekspresi, graffiti  Graffiti is the visual arts the give priority to the game writing , in which letters and words into the chief objects in him .Sleepy is the word to represent an author in created graffiti work. Stems from the desire to elevate graffiti writers as a work of art that encourages graffiti writer raised in the creation of the final project work. The creation of sleepy covering five work with the concept of the different, but there is a connectivity between fifth the concept of are element color.Color which are used in the creation of work use colors is strong and bright.There are two medium used namely the wall and cars.The forging that they used technique spray with aerosol spray paint. Sleepy created from the statement writer living simple but represent expression the deepest writer straight.To the game of colors that are bright writer have hope work graffiti sleepy can entertain eyes road users who was tired by density city. Keywords : SLEEPY , expression , graffit