1,600 research outputs found
Maximum gravitational recoil
Recent calculations of gravitational radiation recoil generated during
black-hole binary mergers have reopened the possibility that a merged binary
can be ejected even from the nucleus of a massive host galaxy. Here we report
the first systematic study of gravitational recoil of equal-mass binaries with
equal, but anti-aligned, spins parallel to the orbital plane. Such an
orientation of the spins is expected to maximize the recoil. We find that
recoil velocity (which is perpendicular to the orbital plane) varies
sinusoidally with the angle that the initial spin directions make with the
initial linear momenta of each hole and scales up to a maximum of ~4000 km/s
for maximally-rotating holes. Our results show that the amplitude of the recoil
velocity can depend sensitively on spin orientations of the black holes prior
to merger.Comment: 4 pages, 4 figs, revtex
Reduksi Warna Methylen Blue (MB) dengan Granular Zeolit Klinoptilolit Teraktivasi
Zat warna metylen blue (MB) merupakan zat warna dasar yang sering digunakan dalam kegiatan industri di Indonesia. Teknologi yang dapat diterapkan dalam aplikasi pengolahan limbah cair yang mengandung MB adalah adosorbsi dengan granular zeolit. Tujuan dalam percobaan ini adalah untuk mengetahui proses adsorpsi dengan menggunakan granular zeolit. Zeolit yang sudah berbentuk granular dicuci selama 24 jam dan diaktivasi dengan penambahan KMnO4. Inisial konsentrasi yang digunakan dalam percobaan ini adalah 1 ppm; 5 ppm10 ppm; 20 ppm; dan 30 ppm. Efisiensi penyisihan warna MB tertinggi adalah 85,49% dengan inisial konsentrasi MB sebesar 5 ppm. Korelasi yang cukup baik dihasilkan pada masing-masing isoterm Langmuir sebesar 0,8248 dan isoterm Freundlich sebesar 0,9523
DESIGN OF CENTRALIZED WASTEWATER SEWERAGE SYSTEM IN SMALL LENGKANG ISLAND, BATAM CITY, INDONESIA
One of the small islands within the Indonesia-Singapore border is Lengkang Island. Wastewater collection infrastructure services on Lengkang Island need to be assessed to improve Sustainable Development Goals (SDGs), where access to wastewater services must reach 100%. The purpose of this study is to determine the existing conditions of wastewater management and to plan a centralized wastewater sewerage system on Lengkang Island involving the community. The existing condition shows that all residents channel wastewater into the sea. Only a few houses have toilets, semi-permanent houses on land. Non-permanent houses built on the sea do not have latrines, where stools are dumped directly into the sea. Tripikon-S is one way to overcome the problem of impermanent homes that do not have latrines. Latrine does not provide a solution to the effects of eutropication. Centralized wastewater collection system and wastewater treatment is one way to overcome this. The results of the planning of wastewater collection systems using PVC pipes mentioned the pipe diameter between 32 mm - 60 mm, with a speed of 0.3 m/sec -1.31 m/sec. With this centralized wastewater sewerage system infrastructure, community participation is expected to increase environmentally friendly development
Pemetaan Pemenuhan Standar Nasional Pendidikan dan Relevansi terhadap Kualitas Pembelajaran dan Ketuntasan Belajar Biologi di Sekolah Menengah Atas
Penelitian bertujuan untuk mengetahui profil pemenuhan standar nasional pendidikan dan hasil ujian nasional serta media dan proses belajar di salah satu sekolah menengah atas kabupaten sukoharjo. Metode yang digunakan dalam penelitian adalah metode survey dengan teknik pengumpulan data melalui angket, wawancara, dan observasi. Hasil penelitian menunjukkan profil keterpenuhan 8 SNP pada salah satu sekolah menengah atas di kabupaten sukoharjo sebesar 83,33 % dengan GAP tertinggi pada standar pendidik dan tenaga kependidikan (3,67 %) dan standar proses (3,24 %). Nilai ujian nasional memiliki rata-rata 5,92 dan pada proses pembelajaran kelas sebesar 81,82 %. Analisis profil buku guru dan siswa secara berturut-turut mendapatkan nilai sebesar 65 % dan 77 %. Hasil profil pemenuhan standar nasional pendidikan, hasil ujian nasional, media, dan proses belajar memberikan informasi yang dapat digunakan sebagai dasar untuk melakukan kegiatan penelitian
New Physics and CP Violation in Singly Cabibbo Suppressed D Decays
We analyze various theoretical aspects of CP violation in singly Cabibbo
suppressed (SCS) D-meson decays, such as . In particular, we
explore the possibility that CP asymmetries will be measured close to the
present level of experimental sensitivity of . Such measurements
would signal new physics. We make the following points: (i) The mechanism at
work in neutral D decays could be indirect or direct CP violation (or both).
(ii) One can experimentally distinguish between these possibilities. (iii) If
the dominant CP violation is indirect, then there are clear predictions for
other modes. (iv) Tree-level direct CP violation in various known models is
constrained to be much smaller than . (v) SCS decays, unlike Cabibbo
favored or doubly Cabibbo suppressed decays, are sensitive to new contributions
from QCD penguin operators and especially from chromomagnetic dipole operators.
This point is illustrated with supersymmetric gluino-squark loops, which can
yield direct CP violating effects of .Comment: 36 pages, 5 figure
Modeling gravitational recoil from precessing highly-spinning unequal-mass black-hole binaries
We measure the gravitational recoil for unequal-mass-black- hole-binary
mergers, with the larger BH having spin a/m^H=0.8, and the smaller BH
non-spinning. We choose our configurations such that, initially, the spins lie
on the orbital plane. The spin and orbital plane precess significantly, and we
find that the out-of plane recoil (i.e. the recoil perpendicular to the orbital
plane around merger) varies as \eta^2 / (1+q), in agreement with our previous
prediction, based on the post-Newtonian scaling.Comment: Published version. 15 pages, 11 figures, revtex
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