On The Synchrotron Self-Compton Emission from Relativistic Shocks and Its Implications for Gamma-Ray Burst Afterglows

We consider the effects of inverse Compton scattering of synchrotron photons from relativistic electrons in GRB afterglows. We compute the spectrum of the inverse Compton emission and find that it can dominate the total cooling rate of the afterglow for several months or even years after the initial explosion. We demonstrate that the presence of strong inverse Compton cooling can be deduced from the effect it has on the time-evolution of the cooling break in the synchrotron spectral component, and therefore on the optical and X-ray afterglow lightcurves. We then show how the physical interpretation of the observed characteristics of the synchrotron spectrum must be modified to take into consideration this extra source of cooling, and give a revised prescription for computing physical parameters characterizing the expanding shock wave from the observed quantities. We find that for a given set of observables (synchrotron break frequencies and fluxes) there is either no consistent physical interpretation or two of them. Finally we discuss the prospects of directly detecting the inverse Compton emission with Chandra. We argue that such a detection is possible for GRBs exploding in a reasonably dense (n>1 cm^-3) medium.Comment: 21 pages, ApJ submitte

Manajemen Kurikulum 2013 oleh Kepala Sekolah

The general purpose of the research was to describe curriculum 2013 management by principle in public Senior High School Number 1 Seluma Regency. The results of the researchwas: (1) planning of curriculum 2013 by principle was done well. (2) organizing the implementation of curriculum 2013 by the principle senior teacher who understand more about curriculum 2013. (3) principle role in succesing the implementation of curriculum 2013 was very vital, he was always held a supervision to his teachers, monitoring and evaluating the progress. (4)the principle in solved the problems faced in implementing curriculum 2013 was downloaded teachers guide and student guide book trought internet and coordinating with vice headmaster and curriculum development team

Eccentricity Evolution for Planets in Gaseous Disks

We investigate the hypothesis that interactions between a giant planet and the disk from which it forms promote eccentricity growth. These interactions are concentrated at discrete Lindblad and corotation resonances. Interactions at principal Lindblad resonances cause the planet's orbit to migrate and open a gap in the disk if the planet is sufficiently massive. Those at first order Lindblad and corotation resonances change the planet's orbital eccentricity. Eccentricity is excited by interactions at external Lindblad resonances which are located on the opposite side of corotation from the planet, and damped by co-orbital Lindblad resonances which overlap the planet's orbit. If the planet clears a gap in the disk, the rate of eccentricity damping by co-orbital Lindblad resonances is reduced. Density gradients associated with the gap activate eccentricity damping by corotation resonances at a rate which initially marginally exceeds that of eccentricity excitation by external Lindblad resonances. But the corotation torque drives a mass flux which reduces the density gradient near the resonance. Sufficient partial saturation of corotation resonances can tip the balance in favor of eccentricity excitation. A minimal initial eccentricity of a few percent is required to overcome viscous diffusion which acts to unsaturate corotation resonances by reestablishing the large scale density gradient. Thus eccentricity growth is a finite amplitude instability. Formally, interactions at the apsidal resonance, which is a special kind of co-orbital Lindblad resonance, appears to damp eccentricity faster than external Lindblad resonances can excite it. However, apsidal waves have such long wavelengths that they do not propagate in protoplanetary disks. This reduces eccentricity damping by the apsidal resonance to a modest level.Comment: Submitted to Ap

Perbedaan Keakraban Suami-istri Berdasarkan Adanya Anak dengan Kecenderungan Attention Deficit/Hyperactivity Disorder

Background: Prevalence of children with Attention Deficit/ Hyperactivity Disorder (ADHD) tendency often funding at school-age. Children with ADHD often make parent feel stress full. Parent will through some energies and time to control children behavior and to find best treatment for children. As a consequence, spouse feels neglected and its will disturb husband-and-wife relationship and threat marriage stability. Husband-and-wife relationship can influence by another socio-demographic factors.Objective: To analyze the difference of husband-and-wife relationship based on children with ADHD tendency existence and another factor i.e communication, sexual intercourse, spouse personality/ temperament, education, occupation, monthly income, marital-age and number of child those give influence heaviness to husband-and-wife relationship.Method: The type of this study is observational with cross sectional analytic design. The subject is parent of student at elementary school of Karangwuni 1 Yogyakarta representatitively by husband or wife by incidental sampling. ADHD tendency is valued by IOWA Conner's Rating Scale instrument. The husband-and-wife relationship is valued by Husband-and-Wife Questioner. Hypothesis tests use chi-square and logistic regression.Result: There is no significant difference of husband-and-wife relationship and children with ADHD tendency (X2 = 1,996; p > 0,05). There is significant difference of education factor and husband-and-wife relationship (p < 0,05; OR = 2,79; CI 1,05-7,47).Conclusion: There is no significant difference of husband-and-wife relationship based on children with ADHD tendency existence for parent of student at elementary school of Karangwuni 1 Yogyakarta. Education factor gives significant influence heaviness to husband-and-wife relationship

Perhitungan Kecepatan Perambatan Gelombang Daerah Bantul Dengan Menggunakan Metode ABC Seismik Refraksi

Telah dilakukan penelitian di daerah Bantul dan sekitarnya dengan menggunakan metode Seismik Refraksi. Tujuan dari penelitian seismik refraksi ini yaitu untuk mengetahui besarnya kecepatan perambatan gelombang lapisan batuan di bawah permukaan pada daerah penelitian. Metode refraksi pada dasarnya memanfaatkan fenomena atau gejala penjalaran gelombang yang terbiaskan pada bidang batas.Kecepatan gelombang seismik pada lapisan pertama dari hasil pengolahan metode ABC dengan range 399 m/s – 1200 m/s yang di indikasikan sebagai lapisan aluvial (soil). Pada lapisan kedua, di peroleh kecepatan gelombang refraksi pada bidang refraktor dengan renge 547 m/s – 2881 m/s yang diindikasikan sebagai batu pasir tuffan

Penerapan Metode Presentasi Ilmiah Berbasis Poster untuk Meningkatkan Keterampilan Berbicara Siswa Kelas V Sekolah Dasar

The research was distributed by associated low speaking skills students in class V SD Negeri Neglasari 01, district Cileunyi, Bandung Regency.&nbsp;Based on the results&nbsp;of observation&nbsp;on the ground&nbsp;that&nbsp;the number&nbsp;of students who are&nbsp;less confident&nbsp;and&nbsp;shywhen speaking&nbsp;in front of the&nbsp;class.&nbsp;This problem&nbsp;is also&nbsp;effected&nbsp;by&nbsp;suboptimal&nbsp;application of&nbsp;models and&nbsp;methods of&nbsp;learning.&nbsp;In addition,&nbsp;the lack of&nbsp;use of&nbsp;media&nbsp;that can improve the&nbsp;learning&nbsp;activities&nbsp;of students&nbsp;at the time of&nbsp;learning.&nbsp;As for the&nbsp;research&nbsp;model&nbsp;used is the&nbsp;class action&nbsp;research&nbsp;(PTK)&nbsp;Jhon&nbsp;Elliot.&nbsp;The research&nbsp;was conducted&nbsp;in three&nbsp;cycles.&nbsp;Each&nbsp;cycle&nbsp;consists of three&nbsp;acts.&nbsp;Research instrument&nbsp;used&nbsp;&nbsp;guidelines&nbsp;assessment,&nbsp;observation&nbsp;sheets, records&nbsp;of field&nbsp;documentation and&nbsp;interview&nbsp;sheet.&nbsp;Data&nbsp;analysis techniques&nbsp;used&nbsp;in this research&nbsp;is&nbsp;quantitative&nbsp;data&nbsp;analysis techniques,&nbsp;qualitative&nbsp;data&nbsp;analysis techniques&nbsp;and&nbsp;triangulation.&nbsp;Based on the research that has been done, the average value of the student's activity cycle I 55.46, cycle II 67.29 and cycle III 78.94. While the average value of speaking skills students cycle I 60.81, cycle II 69.75 and cycle III 80.38.&nbsp;Thus,&nbsp;the&nbsp;results&nbsp;show that&nbsp;the method of&nbsp;presentation of&nbsp;scientifically-based&nbsp;posterscould increase&nbsp;activity and&nbsp;speaking skills&nbsp;of students