44,752 research outputs found
The Impact of Type Ia Supernova Ejecta on Binary Companions
We present adaptive mesh refinement (AMR) hydrodynamical simulations of the
interaction between Type Ia supernovae and their companion stars within the
context of the single-degenerate model. Results for 3D red-giant companions
without binary evolution agree with previous 2D results by Marietta et al. We
also consider evolved helium-star companions in 2D. For a range of helium-star
masses and initial binary separations, we examine the mass unbound by the
interaction and the kick velocity delivered to the companion star. We find that
unbound mass versus separation obeys a power law with index between -3.1 and
-4.0, consistent with previous results for hydrogen-rich companions. Kick
velocity also obeys a power-law relationship with binary separation, but the
slope differs from those found for hydrogen-rich companions. Assuming accretion
via Roche-lobe overflow, we find that the unbound helium mass is consistent
with observational limits. Ablation (shock heating) appears to be more
important in removing gas from helium-star companions than from hydrogen-rich
ones, though stripping (momentum transfer) dominates in both cases.Comment: 6 pages, 2 figures, to appear in the proceedings of the conference
"Binary Star Evolution: Mass Loss, Accretion, and Mergers" at Mykonos,
Greece, June 22-25, 201
Constructing the cultural repertoire in a natural disaster: The role of social media in the Thailand flood of 2011
In 2011, Thailand witnessed its worst flooding catastrophe in half a century. In this study, we explored social media as a new and promising weapon to address the physical and morale challenges caused by the natural disaster. A case study was conducted in the context of crisis response, whichinvestigated the use of social media to contribute to the collective cultural repertoire during the natural disaster. By investigating two paths toward the cultural repertoire construction considering different social groups, this study also identified the roles of social media as an information market and an information threshold in the crisis response
Perlindungan Terhadap Lingkungan Dalam Perspektif Konstitusi
Nowadays there is a tendency in many countries to protect the environment by incorporating general principles of environment into a state or a regional constitution. This article aims to examine the extent to which environmental protection can be provided through the adoption of those constitutional norms. This study was conducted using a qualitative methodology with a normative approach and library research derived from court decisions, law and regulations, books and journal articles. It concludes that the Indonesian Constitution contains constitutional norms for the environmental protection. However, these constitutional norms are still positioned as a subsidiary or supporting factor in the fulfillment of human rights and the national economy. In order to strengthen the environmental protection by the Indonesian Constitution, it requires a reformulation of related constitutional norms by positioning the environment more as the basic values in the state administration and national economic activities
The Protection of Civil and Political Rights by the Constitutional Court of Indonesia
One of important mechanisms considered effective to protect civil and political rights of the citizens in Indonesia is constitutional review. This mechanism was created after the constitutional reform by establishing the new Constitutional Court in 2003 as an independent and separate court from the Supreme Court. This article examines the development of human rights guaranteed in the Indonesian Constitution. It also provides a critical analysis of the Constitutional Court's role in protecting civil and political rights in Indonesia through its landmark decisions on five categories, namely: (1) freedom of assembly and association; (2) freedom of opinion, speech and expression; (3) freedom of religion; (4) right to life; and (5) due process of law. This research was conducted based on qualitative research methodology. It used a non-doctrinal approach by researching the socio-political impacts of the Constitutional Court's decisions. Although there are still inconsistencies in its decisions, the research concludes that the Constitutional Court has taken a step forward for a better protection of civil and political rights in Indonesia that never existed prior to the reform
Dimensi Judicial Activism Dalam Putusan Mahkamah Konstitusi
A transformative amendment of the 1945 Constitution established a separate judicial institution called the Constitutional Court. This institution is believed to serve a strategic role within Indonesia\u27s plural legal system particularly in the area of constitutional review and constitutional rights protection. However, the performance of the Constitutional Court has attracted controversy. This controversy arises because the Court is concerned with introducing a sociological paradigm of law that embraces substantive justice with a fluid acknowledgment of procedural justice. A key criticism of the Constitutional Court is that the nature of Court decisions has developed into a practice of judicial activism. This article discusses the dimension of judicial activism used by the Constitutional Court on the grounds for protecting constitutional rights of the citizens through its decisions. It also analyses the extent of judicial activism that can be justified in the decision-making process in the Constitutonal Court
Memperkuat Prinsip Pemilu yang Teratur, Bebas, dan Adil melalui Pengujian Konstitusionalitas Undang-Undang
Artikel ini membahas peran Mahkamah Konstitusi dalam memperkuat prinsip-prinsip demokrasi di Indonesia, khususnya prinsip Pemilu yang teratur, bebas, dan adil (regular, free and fair elections). Analisis dilakukan terhadap putusan-putusan monumental (landmark decisions) dalam pengujian konstitusionalitas undang-undang yang dikeluarkan oleh Mahkamah Konstitusi terkait dengan penyelenggaraan Pemilu. Penelitian ini didasarkan pada metodologi kualitatif dengan menggunakan studi kepustakaan yang bersumber dari putusan-putusan Mahkamah Konstitusi, peraturan Perundang-undangan, buku, dan artikel jurnal ilmiah. Artikel ini menyimpulkan bahwa Mahkamah Konstitusi telah turut membentuk politik hukum terkait dengan sistem Pemilu di Indonesia dan berbagai aturan pelaksanaannya. Selain itu, Mahkamah Konstitusi juga telah memperkuat prinsip Pemilu yang teratur, bebas, dan adil dengan cara melindungi hak pilih warga negara, menjamin persamaan hak warga negara untuk dipilih, menentukan persamaan syarat partai politik sebagai peserta Pemilu, menyelamatkan suara pemilih, menyempurnakan prosedur pemilihan dalam Pemilu, dan menjaga independensi penyelenggara Pemilu.This article discusses the Constitutional Court's role in strengthening the principles of democracy in Indonesia, particularly the principle of regular, free, and fair elections. An analysis was conducted towards landmark decisions declared by the Constitutional Court regarding general elections. This research is based on qualitative research by undertaking library-based research using the Court's decisions, legislations, books and journal articles. It concludes that the Constitutional Court has established legal policies concerning electoral system in Indonesia and other related implementing regulations. Furthermore, the Constitutional Court has also strengthened the principle of regular, free and fair elections by protecting citizens' right to vote, guaranteeing equal right of citizens to be elected, determining the same requirements for political party participating in the elections, saving citizen's votes, improving electoral procedures and maintaining the independence of election organisers
Antiferromagnetic correlations and impurity broadening of NMR linewidths in cuprate superconductors
We study a model of a d-wave superconductor with strong potential scatterers
in the presence of antiferromagnetic correlations and apply it to experimental
nuclear magnetic resonance (NMR) results on Zn impurities in the
superconducting state of YBCO. We then focus on the contribution of
impurity-induced paramagnetic moments, with Hubbard correlations in the host
system accounted for in Hartree approximation. We show that local magnetism
around individual impurities broadens the line, but quasiparticle interference
between impurity states plays an important role in smearing out impurity
satellite peaks. The model, together with estimates of vortex lattice effects,
provides a semi-quantitative description of the impurity concentration
dependence of the NMR line shape in the superconducting state, and gives a
qualitative description of the temperature dependence of the line asymmetry. We
argue that impurity-induced paramagnetism and resonant local density of states
effects are both necessary to explain existing experiments.Comment: 15 pages, 23 figures, submitted to Phys. Rev.
Quasi-exactly solvable cases of the N-dimensional symmetric quartic anharmonic oscillator
The O(N) invariant quartic anharmonic oscillator is shown to be exactly
solvable if the interaction parameter satisfies special conditions. The problem
is directly related to that of a quantum double well anharmonic oscillator in
an external field. A finite dimensional matrix equation for the problem is
constructed explicitly, along with analytical expressions for some excited
states in the system. The corresponding Niven equations for determining the
polynomial solutions for the problem are given.Comment: 7 pages, RevTeX4. A discussion on the N=1 case has been added with
the boundary condition properly treate
The induced representations of Brauer algebra and the Clebsch-Gordan coefficients of SO(n)
Induced representations of Brauer algebra from with are discussed. The induction coefficients
(IDCs) or the outer-product reduction coefficients (ORCs) of with up to a normalization factor are
derived by using the linear equation method. Weyl tableaus for the
corresponding Gel'fand basis of SO(n) are defined. The assimilation method for
obtaining CG coefficients of SO(n) in the Gel'fand basis for no modification
rule involved couplings from IDCs of Brauer algebra are proposed. Some
isoscalar factors of for the resulting irrep
with
$\sum\limits_{i=1}^{4}\lambda_{i}\leq .Comment: 48 pages latex, submitted to Journal of Phys.
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