696 research outputs found
Scalar soliton quantization with generic moduli
Get PDFThis article is distributed under the terms of the Creative Commons
Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in
any medium, provided the original author(s) and source are credArticle funded by SCOAP3. CP is
a Royal Society Research Fellow and partly supported by the U.S. Department of Energy
under grants DOE-SC0010008, DOE-ARRA-SC0003883 and DOE-DE-SC0007897. ABR
is supported by the Mitchell Family Foundation. We would like to thank the Mitchell
Institute at Texas A&M and the NHETC at Rutgers University respectively for hospitality
during the course of this work. We would also like to acknowledge the Aspen Center
for Physics and NSF grant 1066293 for a stimulating research environment which led to
questions addressed in this paper
A Minimal b Ghost
Get PDFThe b ghost, or b operator, used for fixing Siegel gauge in the pure spinor superfield formalism, is a composite operator of negative ghost number, satisfying (Formula presented.), where q is the pure spinor differential (BRST operator). It is traditionally constructed using non-minimal variables. However, since all cohomology has minimal representatives, it seems likely that there should be versions of physically meaningful operators, also with negative ghost number, using only minimal variables. The purpose of this letter is to demonstrate that this statement holds by providing a concrete construction in (Formula presented.) super-Yang–Mills theory, and to argue that it is a general feature in the pure spinor superfield\ua0formalism
Deformations in Closed String Theory --- Canonical Formulation and Regularization
No full text: We study deformations of closed string theory by primary fields of conformal weight (1; 1), using conformal techniques on the complex plane. A canonical surface integral formalism for computing commutators in a non-holomorphic theory is constructed, and explicit formulae for deformations of operators are given. We identify the unique regularization of the arising divergences that respects conformal invariance, and consider the corresponding parallel transport. The associated connection is metric compatible and carries no curvature. accepted for publication in Nucl.Phys. B. email addresses: [email protected] [email protected] [email protected] Cederwall, von Gussich, Sundell: Deformations in Closed String Theory : : : : : : : : : : : 2 1. Introduction and Summary Probably the most important theoretical problem concerning string theory is the lack of a "covariant" formulation. Despite the fact that closed string theory contains gravity as part of the infinite spectrum, the..
Position sensitivity of segmented planar HPGe detectors for the DESPEC project at FAIR
No full textOne of the proposed germanium detector systems for the upcoming DESPEC array at the FAIR facility consists of triple modules of electrically segmented planar high-purity germanium detectors. In this work, the position sensitivity obtained by means of pulse shape analysis (PSA) for simulated gamma-ray interactions has been studied for the possible segmentation patterns for such detectors-the double-sided strip detector (DSSD) and the one-sided pixelated geometry. An over-all similar number of readout channels has been considered for each case, resulting in 8 + 8 strips and 16 pixels. It has been found that the higher physical granularity of the DSSD results in a significantly higher position resolution, as well as in a somewhat lower probability of merging multiple interaction points. A drawback of the DSSD geometry is the inability to assign the interactions to the correct voxels for certain complex multiple interaction patterns. This effect has been studied in detail. Finally, a comparison has been made with the existing 25-pixel planar detector at KTH [A. Khaplanov, et al., Nucl. Instr. and Meth. A 580 (2007) 1075; L. Milechina, B. Cederwall, Nucl. Instr. and Meth. A 550 (2005) 278)].</p
Lifetime Measurements of Excited States in Pt 172 and the Variation of Quadrupole Transition Strength with Angular Momentum
Get PDF<p>Lifetimes of the first excited 2+ and 4+ states in the extremely neutron-deficient nuclide Pt172 have been measured for the first time using the recoil-distance Doppler shift and recoil-decay tagging techniques. An unusually low value of the ratio B(E2:41+→21+)/B(E2:21+→0gs+)=0.55(19) was found, similar to a handful of other such anomalous cases observed in the entire Segré chart. The observation adds to a cluster of a few extremely neutron-deficient nuclides of the heavy transition metals with neutron numbers N≈90-94 featuring the effect. No theoretical model calculations reported to date have been able to explain the anomalously low B(E2:41+→21+)/B(E2:21+→0gs+) ratios observed in these cases. Such low values cannot, e.g., be explained within the framework of the geometrical collective model or by algebraic approaches within the interacting boson model framework. It is proposed that the group of B(E2:41+→21+)/B(E2:21+→0gs+) ratios in the extremely neutron-deficient even-even W, Os, and Pt nuclei around neutron numbers N≈90-94 reveal a quantum phase transition from a seniority-conserving structure to a collective regime as a function of neutron number. Although a system governed by seniority symmetry is the only theoretical framework for which such an effect may naturally occur, the phenomenon is highly unexpected for these nuclei that are not situated near closed shells.</p>
The B-model on the A-model NS5-brane
No full textWe formulate the dynamics for the NS5-brane of the A-model, via the 'maximal form' method, which couples all background fields to the world-volume. This procedure provides the extra one- and five-forms fields of the extended Hitchin model. The generalised B-model emerges as the world-volume theory of this brane. The starting point of the construction is an embedding of the brane in a superspace geometry with 16 fermionic directions. The correspondence with Hitchin's formulation in terms of pure spinors is explained
The B-model on the A-model NS5-brane
No full textWe formulate the dynamics for the NS5-brane of the A-model, via the 'maximal form' method, which couples all background fields to the world-volume. This procedure provides the extra one- and five-forms fields of the extended Hitchin model. The generalised B-model emerges as the world-volume theory of this brane. The starting point of the construction is an embedding of the brane in a superspace geometry with 16 fermionic directions. The correspondence with Hitchin's formulation in terms of pure spinors is explained
Evidence of octupole-phonons at high spin in Pb-207
No full textA lifetime measurement of the 19/2(-) state in Pb-207 has been performed using the Recoil Distance Doppler-Shift (RDDS) method. The nuclei of interest were produced in multi-nucleon transfer reactions induced by a Pb-208 beam impinging on a Mo-100 enriched target. The beam-like nuclei were detected and identified in terms of their atomic mass number in the VAMOS++ spectrometer while the prompt gamma rays were detected by the AGATA tracking array. The measured large reduced transition probability B(E3, 19/2(-) -> 13/2(+)) = 40(8) W.u. is the first indication of the octupole phonon at high spin in Pb-207. An analysis in terms of a particle-octupole-vibration coupling model indicates that the measured B(E3) value in Pb-207 is compatible with the contributions from single-phonon and single particle E3 as well as E3 strength arising from the double-octupole-phonon 6(+) state, all adding coherently. A crucial aspect of the coupling model, namely the strong mixing between single-hole and the phonon-hole states, is confirmed in a realistic shell-model calculation. Crown Copyright B.V.</p
Encounter with religion in the game world : A representation analysis of Shinto and Buddhism in Ghost of Tsushima
No full textIn this essay, the author examines religion and how it is represented in the video game Ghost of Tsushima. With the representation term and its meaning from Stuart Hall, the author aims to analyse religious aspects in the game’s environment and story, thus in the end picking out the representation that the games create of religion. Using qualitative content analysis and semiotics, the author picks out temples, monks, amulets, and Kami as the main religious aspects that are found in-game. As it turns out the religious aspects in-game create the impression of Buddhist overturn in the Shinto religion. Many aspects stem from Buddhism, which correlate to the period and how Shinto assimilated Buddhist practises over time. The monks and temples are all of Buddhist origin, except for the official shrines to the Kami in-game. Overall, the Kami and Shinto, in general, are not present beyond being used for mechanics in the game while Buddhism is represented with more important aspects with major characters and meanings shown or talked about. The author does note that both religious traditions are presented more as merged, having become indistinguishable during the period in accordance with historical research. The essay concludes thus that religion is mostly represented in the characters like the warrior monk Norio and the monk Junshin who are followed more closely and represent religion through their actions and words
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