Correlated Spectral And Temporal Behaviour Of Late-Time Afterglows Of Gamma Ray Bursts

The cannonball (CB) model of gamma ray bursts (GRBs) predicts that the asymptotic behaviour of the spectral energy density of the X-ray afterglow of GRBs is a power-law in time and in frequency where the difference between the temporal and spectral power-law indexes, $\alpha_X-\beta_X$, is restricted to the values 0, 1/2 and 1. Here we report the distributions of the values $\alpha_X$, $\beta_X$ and their difference for a sample of 315 Swift GRBs. This sample includes all Swift GRBs that were detected before August 1, 2012, whose X-ray afterglow extended well beyond 1 day and the estimated error in $\alpha_X-\beta_X$ was $\leq 0.25$. The values of $\alpha_X$ were extracted from the CB model fits to the entire light curves of their X-ray afterglow while the spectral index was extracted by the Swift team from the time integrated X-ray afterglow of these GRBs. We found that the distribution of the difference $\alpha_X-\beta_X$ for these 315 Swift GRBs has three narrow peaks around 0, 1/2 and 1 whose widths are consistent with being due to the measurement errors, in agreement with the CB model prediction.Comment: 12 figures, added references, used data reported in the Swift/XRT light-curve repositor

A solution of a hoary conundrum: the origin and properties of cosmic rays

I discuss a theory of non-solar cosmic rays (CRs) based on a single type of CR source at all energies. All observed properties of CRs are predicted in terms of very simple and completely `standard' physics. The source of CRs is extremely `economical': it has only one parameter to be fitted to the enormous ensemble of all of the data. All other inputs are `priors', that is theoretical or observational items of information independent of the properties of the source of CRs and chosen to lie in their pre-established ranges.Comment: 10 pages, 13 figures. Contribution to the Cosmic Ray International Seminar, Catania, 200

The Anticipated Supernova Associated with GRB090618

We use the cannonball model of gamma ray bursts (GRBs) and public data from the first day of observations of GRB 090618 to predict its X-ray and optical lightcurves until very late times, and, in particular, the emergence of a photometric and spectroscopic signature of an SN akin to SN1998bw in its optical afterglow with an anticipated peak brightness of magnitude 23 in the R band around July 10, 2009, if extinction in the host galaxy can be neglected.Comment: 10 pages, 2 Figure

Keefektifan Pengelolaan Laboratorium IPA SMP/MTs di Kabupaten Nagekeo, Propinsi Nusa Tenggara Timur

Penelitian ini bertujuan untuk mengetahui: (1) keefektifan pengelolaan laboratorium IPA SMP/MTs di Kabupaten Nagekeo, dan (2) keefektifan pengelolaan laboratorium yang menghasilkan keefektifan pembelajaran IPA, yang dilihat melalui perencanaan, pengorganisasian, pelaksanaan, pengawasan dan evaluasi pengelolaan laboratorium IPA, dan nilai ujian nasional mata pelajaran IPA tahun 2008. Penelitian ini merupakan penelitian survei terhadap populasi 3 SMP/MTs di Kabupaten Nagekeo. Subjek penelitian terdiri dari: kepala sekolah sebanyak 3 responden, koordinator laboratorium sebanyak 3 responden, guru IPA, laboran sebanyak 5 responden dan peserta didik kelas IX tahun pelajaran 2008/2009 sebanyak 168 responden. Pengumpulan data menggunakan observasi, wawancara, dokumentasi dan angket. Pengujian validitas instrument dilakukan dengan metode korelasi. Analisis data dilakukan dengan menggunakan teknik deskriptif kualitatif. Hasil penelitian menunjukkan bahwa: (1) pengelolaan laboratorium IPA SMP/MTs di Kabupaten Nagekeo adalah cukup efektif, yang didukung oleh perencanaan efektif, pengorganisasian kurang efektif, pelaksanaan cukup efektif, pengawasan dan evaluasi kurang efektif, dan (2) keefektifan pengelolaan laboratorium cenderung menghasilkan pembelajaran IPA yang efektif

Flares In Long And Short Gamma Ray Bursts

The many similarities between the prompt emission pulses in gamma ray bursts (GRBs) and X-ray flares during the fast decay and afterglow phases of GRBs suggest a common origin. In the cannonball (CB) model of GRBs, this common origin is mass accretion episodes of fall-back matter on a newly born compact object. The prompt emission pulses are produced by a bipolar jet of highly relativistic plasmoids (CBs) ejected in the early, major episodes of mass accretion. As the accretion material is consumed, one may expect the engine's activity to weaken. X-ray flares ending the prompt emission and during the afterglow phase are produced in such delayed episodes of mass accretion. The common engine, environment and radiation mechanisms (inverse Compton scattering and synchrotron radiation) produce their observed similarities. Flares in both long GRBs and short hard gamma ray bursts (SHBs) can also be produced by bipolar ejections of CBs following a phase transition in compact objects due to loss of angular momentum and/or cooling. Optical flares, however, are mostly produced in collisions of CBs with massive stellar winds/ejecta or with density bumps along their path. In this paper we show that the master formulae of the CB model of GRBs and SHBs, which reproduce very well their prompt emission pulses and their smooth afterglows, seem to reproduce also very well the lightcurves and spectral evolution of the prominent X-ray and optical flares that are well sampled.Comment: Added new section on optical flares, 3 tables and 5(x6) multiple figures comparing observations and theor