Dissertations / Theses: 'Chandrian'

1

Bhowmik, Shefali. "Bangla Upanyase Prem o Bibaha:Bankim Chandra-Rabindra Nath-Sharat Chandra বাংলা উপন্যাসে প্রেম ও বিবাহ : বঙ্কিমচন্দ্র - রবীন্দ্রনাথ -শরৎচন্দ্র." Thesis, University of North Bengal, 1998. http://hdl.handle.net/123456789/1652.

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Kakati, Jogesh. "Subhas Chandra Bose and the British Raj." Thesis, University of North Bengal, 2005. http://hdl.handle.net/123456789/1249.

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3

Otto, Tobias [Verfasser], Madhukar [Akademischer Betreuer] Chandra, Madhukar [Gutachter] Chandra, Gerd [Gutachter] Wanielik, and Martin [Gutachter] Hagen. "Propagation effects influencing polarimetric weather radar measurements / Tobias Otto ; Gutachter: Madhukar Chandra, Gerd Wanielik, Martin Hagen ; Betreuer: Madhukar Chandra." Chemnitz : Universitätsbibliothek Chemnitz, 2011. http://d-nb.info/1213904889/34.

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4

Maurya, Devalāla. "Hindī sāhitya kā itihāsa-darśana aura Rāmacandra Śukla /." Ilāhābāda : Eksīlensa pabliśarsa, 1993. http://catalogue.bnf.fr/ark:/12148/cb36190705w.

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5

Dalla, Mura Maria Elisabetta. "Ricerca di AGN oscurati nei Chandra Deep Fields." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/9893/.

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La forma spettrale dell’X-ray background richiede l’esistenza di un grande numero di AGN mediamente oscurati, oltre alla presenza di AGN fortemente oscurati, la cui densità di colonna supera il limite Compton (Nh>10^24 cm^(-2)). A causa della loro natura, questi oggetti risultano di difficile osservazione, per cui è necessario adottare un approccio multi-banda per riuscire a rivelarli. In questo lavoro di tesi abbiamo studiato 29 sorgenti osservate nel CDF-S e 10 nel CDF-N a 0.0710^23, spettro piatto, riga del ferro): a seguito di questa analisi sono state individuate 9 sorgenti che presentano indicazioni di forte oscuramento. Dallo studio del rapporto tra la luminosità X (2-10 keV) e quella MIR (12.3um) dedotta dal SED-fitting, si è ottenuta una conferma della possibile presenza di forte oscuramento nelle 9 sorgenti selezionate a seguito dell’analisi spettrale. Abbiamo inoltre confrontato il tasso di formazione stellare dedotto dalla banda X (0.5-8 keV) e da quella IR (8-1000um) per identificare le sorgenti nelle quali l’emissione da AGN risulta essere dominante. A seguito di questa analisi abbiamo identificato 9 sorgenti (le stesse di cui sopra) con indicazione di forte oscuramento; di queste, 3 mostrano chiare indicazioni della presenza di un AGN Compton Thick (Nh>10^24 cm^(-2), riga del ferro intensa, basso rapporto LX/MIR).

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Phruksahiran, Narathep [Verfasser], Madhukar [Akademischer Betreuer] Chandra, Madhukar [Gutachter] Chandra, and Gerd [Gutachter] Wanielik. "Polarimetrische Streuungseigenschaften und Fokussierungsmethoden zur quantitativen Auswertung der polarimetrischen SAR-Daten / Narathep Phruksahiran ; Gutachter: Madhukar Chandra, Gerd Wanielik ; Betreuer: Madhukar Chandra." Chemnitz : Universitätsbibliothek Chemnitz, 2013. http://d-nb.info/121424520X/34.

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7

Aqbi, Sadiq [Verfasser], Madhukar [Akademischer Betreuer] Chandra, Madhukar [Gutachter] Chandra, and Ian Andrew [Gutachter] Glover. "Improving the Performance of Dual Linear Polarization Antennas with Metamaterial Structures / Sadiq Aqbi ; Gutachter: Madhukar Chandra, Ian Andrew Glover ; Betreuer: Madhukar Chandra." Chemnitz : Universitätsbibliothek Chemnitz, 2018. http://d-nb.info/121464984X/34.

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8

Ibba, Tiziana. "Chandra investigation of 3CRR radio sources at high redshift." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/20023/.

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In this thesis the main goal is to investigate the nuclear regions of high-redshift AGN, in order to characterize their X-ray properties and make a comparison with sources at lower redshifts. In the local Universe, a correlation between accretion estimated with the X-ray luminosity between 2-10keV and with the [OIII] IR emission, has been inferred. It is intriguing to observe if this is still valid for the AGN at high redshifts, even if the observation for this sources are more challenging. For this purpose, I proceeded reducing and analysing the X-ray data available in the Chandra public archive for all the sources at z>1 in the 3CRR catalog. This catalog is well observed in all the spectral range, but the X-ray band permits the investigation of the nuclear energetic processes at scales ranging from the kpc to (less than)pc. In addition, a systematic qualitative imaging has been used has a guiding tool during the analysis. In two sources a clear sign of rich environment was visible. Almost all the objects were well represented by a simple absorbed power law model, with the exception of three objects which showed other features (i.e., the Fe line and a thermal component). The luminosity obtained were compared to the [OIII] and they showed a discrepancy. Being aware of the observational limits in the X-ray band and suspecting an observational bias, an investigation based on the IR absorption was carried on. From this scrutiny emerged that most of the radio galaxies, due to their complexity, are more absorbed than the X-ray analysis managed to find. Assuming the existence of this bias and removing the biased objects from the sample, the X-ray and O[III] luminosity are in agreement. Doing a comparison with the radio galaxies at lower redshift studied by Macconi et al. (2020), the objects in my sample successfully reproduce the same correlation, shifted at higher accretion values.

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Rutherford, John (John Morton). "Imaging X-ray spectroscopy with micro-X and Chandra." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/84183.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2013.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 245-258).
High spectral resolution observations of X-ray phenomena have the potential to uncover new physics. Currently, only point sources can be probed with high resolution spectra, using gratings. Extended objects like supernova remnants cannot be dispersed, leaving the dense forest of emission lines blended by the moderate resolution of modern instruments. In the first half of this thesis, I undertake two investigations of the supernova remnant Cassiopeia A using the flagship X-ray observatory, Chandra. The first study combines the spatial resolution of the ACIS instrument with the spectral resolution of the dispersive HETG to investigate the evolution of ejecta knots. The second improves on statistical limits of radioactive ejecta, and simulates what higher resolution instruments may observe. Micro-X, a new high resolution X-ray telescope, is the focus of the second half. I detail the commissioning of this novel sounding rocket payload, which uses a focal plane of micro-calorimeters to achieve high spectral resolution in each pixel. The flight hardware is in a final state of testing and integration before the launch, which is anticipated in 2014.
by John Rutherford.
Ph.D.

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10

Rosignoli, Luca. "Analisi dettagliata di nuove osservazioni Chandra di Abell 2495." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amslaurea.unibo.it/25297/.

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Questo lavoro di tesi consiste in uno studio in banda X dell'ammasso di galassie Abell 2495 (z~0.079), basato sull'analisi dettagliata di nuove osservazioni del telescopio spaziale Chandra della durata di ~130 ks. Sono stati confermati alcuni dei risultati trovati in precedenza da uno studio basato su una singola esposizione di ~8 ks. In particolare, la presenza di due offset spaziali: il primo tra il picco di emissione X e la radio galassia centrale (~6 kpc), mentre il secondo tra il picco di emissione Hα e quello X (~4 kpc). Inoltre, sono state osservate due coppie di depressioni in brillanza, simili a quelle trovate in precedenza e supposte essere cavità scavate dai getti radio dell'AGN centrale. In particolare, una coppia risulta vicina all'AGN, con un raggio di r~3 kpc, mentre la seconda si trova più esternamente, in contrapposizione rispetto al picco di emissione X e con un raggio di ~5 kpc. Infine, dall'analisi morfologica è emersa una possibile discontinuità nel profilo di brillanza, successivamente identificata come cold front dovuta all'oscillazione del gas. L'analisi spettrale ha permesso di creare i profili delle quantità termodinamiche del gas con una risoluzione e una statistica molto maggiori rispetto al lavoro precedente. Eseguendo un bilancio energetico tra la potenza delle cavità e la luminosità entro il raggio di cooling è emerso che l'energia immessa dall'AGN è capace di controbilanciare il raffreddamento del gas, sebbene la presenza di offset tra il picco di emissione X e l'AGN centrale possa compromettere il ciclo di AGN feedback. In questo contesto l'interpretazione preferita risulta essere quella basata sul fenomeno di oscillazione del gas (sloshing) la cui periodicità potrebbe attivare l'AGN, mantenendo così il ciclo di feedback. Questo scenario, che è in grado di spiegare la presenza degli offset osservati, è supportato dal fatto che la stima del tempo di oscillazione risulta consistente con la differenza di età delle due coppie di cavità.

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11

Som, Sarkar Dipika. "Iswar Chandra Gupter kabya bhasha ঈশ্বরচন্দ্র গুপ্তের কাব্য-ভাষা." Thesis, University of North Bengal, 1991. http://hdl.handle.net/123456789/1776.

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12

Eckmiller, Helen [Verfasser]. "Testing X-Ray Scaling Relations with a Sample of Chandra Galaxy Groups and Detailed Analysis of A2244 with Chandra and Suzaku / Helen Eckmiller." Bonn : Universitäts- und Landesbibliothek Bonn, 2012. http://d-nb.info/1044081880/34.

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13

Vollbracht, Dennis [Verfasser], Madhukar [Akademischer Betreuer] Chandra, Madhukar [Gutachter] Chandra, and Dirk [Gutachter] Fischer. "Design and development of phased-array antennas for dual-polarized weather radar applications / Dennis Vollbracht ; Gutachter: Madhukar Chandra, Dirk Fischer ; Betreuer: Madhukar Chandra." Chemnitz : Universitätsverlag Chemnitz, 2019. http://d-nb.info/1219664766/34.

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14

Zichner, Ralf [Verfasser], Madhukar [Akademischer Betreuer] Chandra, Madhukar [Gutachter] Chandra, Reinhard R. [Akademischer Betreuer] Baumann, and Reinhard R. [Gutachter] Baumann. "Hochfrequenz‐Kommunikation gedruckter Antennen in herausfordernden dielektrischen oder metallischen Umgebungen / Ralf Zichner ; Gutachter: Madhukar Chandra, Reinhard R. Baumann ; Madhukar Chandra, Reinhard R. Baumann." Chemnitz : Universitätsbibliothek Chemnitz, 2013. http://d-nb.info/1214245935/34.

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15

Debnath, Sailen. "Netaji Subhas Chandra Bose and secularism : his ideas and activities." Thesis, University of North Bengal, 1986. http://hdl.handle.net/123456789/1221.

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16

Bhattacharya, Rama. "A critical approach to the short stories of Jagadish Chandra Gupta." Thesis, University of North Bengal, 1989. http://hdl.handle.net/123456789/1199.

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17

Bertola, Elena. "The Chandra and XMM-Newton views of the Einstein Cross." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17624/.

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La caratterizzazione dell'AGN feedback è ancora un problema aperto. Uno dei possibili modi in cui l'AGN potrebbe influire sull'evoluzione della galassia ospite è attraverso la generazione di potenti venti dalle zone più interne del disco (Ultra Fast Outflows, UFOs), visti nel ~50% degli AGN vicini. Per quanto riguarda le sorgenti ad alto redshift, si hanno ancora poche detezioni di questi venti, anche se si pensa che siano altrettanto comuni. Come lavoro di tesi, ho analizzato tutti i dati in banda X disponibili per l'Einstein Cross, un quasar a z~1.7 lensato in quattro immagini da una galassia a spirale a z~0.04. Questo lavoro rappresenta la prima analisi spettrale di questa sorgente per la quale si utilizzano sia dati Chandra (35 obs., immagini risolte) che dati XMM (tre obs.) combinando le peculiarità di entrambi i telescopi. Utilizzando un semplice modello di legge di potenza più assorbimento galattico, i dati Chandra hanno permesso di scoprire che la sorgente mostra variabilità spettrale tra i vari puntamenti. Ho investigato limitando l'analisi agli spettri a più alta statistica, 14 spettri Chandra, 2 XMM (2002, 2018). Dai dati Chandra è stato possibile osservare che la sorgente presenta un assorbitore a densità di colonna variabile. Detectiamo per la prima volta caratteristiche feature di Ultra Fast Outflows (UFOs) in 9 di questi 16 spettri, da cui ricaviamo una grezza stima del wind duty cycle, il cui limite inferiore è pari a ~50%. I dati XMM del 2002 sono meglio riprodotti da un assorbitore spesso, molto ionizzato e in outflow a ~0.1c, di potenza cinetica ~1.3dex della luminosità bolometrica. Dati i modelli attuali, questo vento sembrerebbe abbastanza energetico da incidere sensibilmente sull'evoluzione della galassia ospite. I dati XMM del 2018 invece non mostrano segni caratteristici di una componente di outflow molte veloce, ma son meglio riprodotti da un assorbitore freddo, abbastanza spesso, consistente con le zone più interne del toro molecolare.

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Hollowood, Devon. "Cosmological Studies through Large-Scale Distributed Analysis of Chandra Observations." Thesis, University of California, Santa Cruz, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10973254.

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The formation history of galaxy clusters is a powerful probe of cosmology. In particular, one may place strong constraints on the dark energy equation of state by examining the evolution across redshift of the number density of galaxy clusters as a function of mass. In this thesis, I describe my contributions to cluster cosmology, in particular to the development of the richness optical observable mass proxy.

I introduce redMaPPer, an optical cluster finder which represents an important upstream input for my thesis work. I next introduce the Mass Analysis Tool for Cha ndra (MATCha), a pipeline which uses a parallelized algorithm to analyze archival Chandra data. MATCha simultaneously calculates X-ray temperatures and luminosities and performs centering measurements for hundreds of potential galaxy clusters using archival X-ray exposures. I run MATCha on the redMaPPer SDSS DR8 cluster catalog and use MATCha's output X-ray temperatures and luminosities to analyze the galaxy cluster temperature-richness, luminosity-richness, luminosity-temperature, and temperature-luminosity scaling relations. I investigate the distribution of offsets between the X-ray center and redMaPPer center within 0.1 < z < 0.35 and explore some of the causes of redMaPPer miscentering. I collaborate with members of the Dark Energy Survey in order to repeat this analysis on Dark Energy Survey Year 1 data. I outline the various ways in which MATCha constitutes an important upstream work for a variety of astrophysical applications. These include the calibrations of two separate mass proxies, the study of the AGN fraction of galaxy clusters, and cosmology from cluster number densities and stacked weak lensing masses. Finally, I outline future upgrades and applications for MATCha throughout the lifespan of the Dark Energy Survey and the Large Synoptic Survey Telescope.

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Bartolini, Chiara. "Proprietà termiche della galassia Jellyfish JO194 derivate da un'osservazione Chandra." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/24939/.

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Le galassie che mostrano i risultati più evidenti dell'azione del ram pressure stripping, sotto forma di lunghe scie di gas proveniente dal loro disco, vengono chiamate jellyfish. La survey GAs Stripping Phenomena (GASP), eseguita con lo spettrografo a campo integrale MUSE del VLT, si occupa di esaminare 114 galassie a spirale soggette a ram pressure stripping, collocate in gruppi o ammassi ad un redshift compreso tra $0.04-0.07$,. In questo lavoro di Tesi viene mostrata un'analisi X delle proprietà termiche della galassia jellyfish JO194 (z=0.041), proveniente dal campione GASP e collocata nell'ammasso Abell 4059 (z=0.048). Grazie alle caratteristiche dell'osservazione, è stato possibile analizzare le proprietà spettrali dell'ammasso e della galassia. Dall'analisi spettrale risulta che l'emissione complessiva della galassia sia prodotta da un plasma multi-temperatura, mentre la sola emissione X del disco stellare è consistente con un gas monotermo ionizzato tramite collisioni. Uno dei risultati più innovativi di questo lavoro, viene dall'analisi dell'emissione della coda di JO194. Troviamo infatti che questa regione corrisponde a quella di un gas in raffreddamento di cui, per la prima volta, si è potuto ricavare la metallicità. Questo risultato suggerisce che il plasma caldo in raffreddamento sia ICM infiltratosi all'interno di JO194. Da questa analisi risulta, quindi, che disco stellare e braccia si trovino in condizioni differenti. Per identificare l'origine del gas caldo diffuso presente all'interno di JO194, si è confrontato il tasso di formazione stellare totale e del solo disco stellare ricavato dall'analisi con quello di uno studio precedente. Da questo confronto risulta che i due tassi sono consistenti tra loro solo nel caso del disco. Sulla base di questo possiamo concludere che nella parte esterna al disco sia presente una sorgente ulteriore di emissione X che non è direttamente legata alla formazione stellare.

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20

PAPALEXIOU, NIKOLAOS. "Sur la methode des orbites et l'homomorphisme de harish-chandra." Paris 7, 1998. http://www.theses.fr/1998PA077119.

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Soient g une algebre de lie semi-simple complexe, g son groupe adjoint algebrique, h une sous-algebre de cartan de g et w le groupe de weyl associe. Dans ce travail, nous etudions l'extension de l'homomorphisme de harish-chandra a l'algebre des operateurs differentiels sur g, a coefficients series formelles a(g)#g a(h)#w. Soient u(g) l'algebre enveloppante de g et g*#r l'ensemble des elements reguliers du dual g*. Suivant une idee de j. Dixmier, nous construisons une bijection de l'ensemble g*#r/g des orbites regulieres sur l'ensemble $$ des ideaux minimaux de u(g), sans utiliser la notion de polarisation.

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21

Hanisch, Christoph. "Why the Law matters to you: Citizenship, Agency, and Public Identity." Bowling Green State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1339933456.

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22

Khan, Akbar Ali. "Netaji Subash Chandra Bose and the provisional government of Azad Hind-an analytical construction." Thesis, University of North Bengal, 2003. http://hdl.handle.net/123456789/1200.

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23

Hui, Chung Yue. "X-Ray Observations of Neutron Stars with XMM-Newton & Chandra." Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-89872.

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Gonzalez, Edgar Raul 1977. "Results from five Chandra observations of the normal galaxy NGC 3877." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/32740.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2004.
Includes bibliographical references (p. 67-72).
We present the results of five Chandra observations of the normal galaxy NGC 3877. A total of 27 X-ray sources are detected, including SN 1998S. We find 15 sources to be variable during the 646-day period covered by the observations. We use two methods to determine source color and find no apparent correlation between color and brightness in our population sample. We provide flux and luminosity estimates for every source and construct cumulative X-ray luminosity functions (XLFs) for each observation. We find a higher density of luminous ([approximately] 10³⁷ erg s⁻¹) sources in NGC 3877 than we see in two other galaxies. We tentatively identify some sources as X-ray binaries.
by Edgar Raul Gonzalez.
S.B.

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25

Stevens, J. A. "Colonial subjectivity : Keshab Chandra Sen in London and Calcutta, 1870-1884." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1333989/.

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The thesis investigates the ideas and activities of the Bengali Brahmo religious and social reformer Keshab Chandra Sen, and his interaction with a range of British intellectual, political and cultural figures. Keshab propounded novel and influential ideas regarding the relations between ‘East’ and ‘West’ to audiences in Britain and India (concerning British rule in India, education, religion and spirituality, the position of women, global history, universalism and modernity), ideas that were profoundly shaped by his experiences as a colonial subject in two powerful centres of empire - London and Calcutta. The thesis draws upon approaches from biographical, intellectual, social, cultural and political history in order to locate Keshab within an analysis which relates the construction of identity in public discourses in multiple sites of empire to an analysis of the experience of colonial subjectivity at the level of friendship, family and self. This analysis is grounded in an exploration of the social construction of notions of ‘difference’, with particular reference to ideas of race, gender, class and nation. Through bringing London and Calcutta into a single analytic frame, the thesis demonstrates the ways in which encounters between subjects from metropole and colony, and the representations of these encounters in both the metropole and the colony, shaped identities in an imperial context. The thesis pays particular attention to the sustained inter-cultural dialogue between Keshabite Brahmoism and British Unitarianism. Discourses of universalism in Britain and Bengal are analyzed as they developed in relation to each other, a relation that was limited and reconfigured by inequalities of power immanent in imperialism. The thesis brings Brahmo and Unitarian universalism into a postcolonial focus, and rematerializes Keshab within a genealogy of Bengali intellectual history which is itself tied to universalist discourses in the imperial metropole.

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Chandrasekharan, Nair Vinod Chandran [Verfasser], and Martin [Akademischer Betreuer] Jansen. "Heteronuclear spin decoupling sequences with frequency sweep in solid-state NMR spectroscopy / Vinod Chandran Chandrasekharan Nair. Betreuer: Martin Jansen." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2012. http://d-nb.info/1021343560/34.

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Ignesti, Alessandro. "A combined JVLA and Chandra study of the Abell 2626 galaxy cluster." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12817/.

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In this thesis work we carried out an accurate analysis of new observations of the galaxy cluster Abell 2626 in the radio and X-ray bands. Its radio emission is characterized by the presence of a system of peculiar radio sources, the arcs , whose properties differs from the properties of the common cluster diffuse radio sources. In the past years, several models have been proposed to explain their origin. Our work aims at investigating the origin of the arcs. We analyzed new JVLA observations of the cluster at 3.0 GHz and 5.5 GHz. During the radio analysis we detected the arcs at 3.0 GHz and possible evidences for extended emission inside them at 5.5 GHz. By combining archival maps at 1.4 GHz and the new ones at 3.0 GHz, we estimated that the arcs have a spectral index α ∼ -3. The analysis of a new CHANDRA observation of the cluster produced surprising results. We highlighted the a spatial connection between the radio arcs and a cold region inside the cluster core and, moreover, we discovered a cold front which coincides with the south-west junction of the radio arcs. It is well known that the turbulence inside the cold fronts is able to accelerate the relativistic particles, triggering radio emission in form of mini-halos. Under certain conditions, this emission results in form of collimated steep-spectrum arcs that traces the dynamics of the cold fronts. So we proposed a scenario, in which the arcs are not related to the precession of AGN jets, but instead are produced by non-thermal processes (particle acceleration and magnetic fled amplification) that are related to the formation and the evolution of the cold fronts in the core of Abell 2626. In this case the peculiar morphology of the arcs is the result of the dynamics of the cold fronts, that will be studied with future MHD simulations.

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Guerra, Raffaella. "Studio della variabilità dal centro galattico in 14 anni di osservazioni Chandra." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12935/.

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Nelle regioni centrali della Via Lattea è presente una grande varietà di popolazioni stellari, fra cui remnant di stelle massicce come stelle di neutroni e buchi neri. Questi oggetti possono trovarsi all'interno di sistemi binari in cui accrescono materia dall'oggetto compatto e vengono denominate X-Ray Binaries (XRB). Le XRB trascorrono la maggior parte della loro vita in fase quiescente, ma occasionalmente possono mostrare burst molto brillanti (su tempi scala di mesi/anni), durante i quali la loro luminosità può aumentare anche più di un fattore 100. Lo studio delle XRB nelle regioni centrali della nostra galassia è fondamentale non solo perchè consente di trarre informazioni sulle proprietà di Sgr A*, il buco nero supermassiccio centrale, ma anche per investigare ancora più nel dettaglio la fisica di accrescimento di questi oggetti. Infatti alcuni meccanismi di emissione di queste binarie ancora non vengono compresi, come succede per le Faint X-Ray Binaries (FXRB) e le Very Faint X-Ray Binaries (VFXRB): queste sorgenti mostrano luminosità molto minori rispetto a quelle normalmente associate a queste sorgenti. Sfruttando le osservazioni compiute tramite la camera ACIS-I di Chandra fra il 1999 e il 2013, la nostra ricerca si pone come obiettivo quello di rilevare sorgenti transienti deboli all'interno di una regione quadrata 5x5 arcmin centrata su Sgr A*, che comprende Sgr A e le zone di influenza del SMBH. Nella prima parte di questo lavoro stileremo un catalogo di sorgenti rivelate all'interno della regione da noi analizzata e fra queste si cercherà di identificare quelle transienti. Per ciascuna delle sorgenti ritenute variabili, verrà inoltre creata una curva di luce che potrà servire come riferimento per stimare i tempi di burst e per chiarire, in futuro, la natura di queste sorgenti.

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29

Pekon, Yakup. "Analysis Of Chandra Data Of The Old Classical Nova Rr Pic (1925)." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608716/index.pdf.

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In this work, the CHANDRA ACIS-S3 data of the old classical nova RR Pic (1925) is presented. The source is detected with a count rate of 0.067 (+-0.002) c/s in the 0.3-5.0 keV energy range. The orbital period of the binary system in X-ray wavelengths is detected. X-ray spectrum of RR Pic can be represented by a composite model of bremsstrahlung with a photoelectric absorption, two absorption lines centered around 1.1-1.4 keV and 5 Gaussian emission lines centered at around 0.3-1.1 keV . The best t bremsstrahlung temperature derived from the model ranges from 0.99 to 1.60 keV and the unabsorbed X-ray flux is found to be 2.51 (+0.39 -1.21) erg/cm2/s in the 0.3-5.0 keV range.The absorption lines correspond to several transitions of Fe, Ne and Na. The emission lines correspond to various transitions of S, N, O, C, Ne and Fe
and observations with better spectral resolution are needed to determine the exact transitions. The source spectrum is better explained with photoionized plasma model rather than the cooling flow model. It has also been found that the neutral Hydrogen column density differs for orbital minimum and orbital maximum spectra with values 0.25 (+0.23 -0:18)*10^22 atoms/cm2 and 0.64 (+0.13 -0.14)*10^22 atoms/cm2 respectively at 3 sigma confidence level. The difference of neutral Hydrogen column density between the maximum and minimum phase spectra indicates existence of a warm absorbing region on the disc at the location of the impact zone.

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Shrestha, Jyoti Chandra [Verfasser]. "Theoretical and experimental study of intracavity laser absorption spectroscopy / Jyoti Chandra Shrestha." Kassel : Universitätsbibliothek Kassel, 2015. http://d-nb.info/1069569550/34.

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Thakur, Harish Chandra [Verfasser]. "Biochemical and biophysical characterization of the centrosomal protein TACC3 / Harish Chandra Thakur." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2013. http://d-nb.info/1036727491/34.

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Kraev, Urmila Mitra. "Flares on active M-type stars observed with XMM-Newton and Chandra." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1444852/.

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M-type red dwarfs are among the most active stars. Their light curves display random variability of rapid increase and gradual decrease in emission. It is believed that these large energy events, or flares, are the manifestation of the permanently reforming magnetic field of the stellar atmosphere. Stellar coronal flares are observed in the radio, optical, ultraviolet and X-rays. With the new generation of X-ray telescopes, XMM-Newton and Chandra, it has become possible to study these flares in much greater detail than ever before. This thesis focuses on three core issues about flares: (i) how their X-ray emission is correlated with the ultraviolet, (ii) using an oscillation to determine the loop length and the magnetic field strength of a particular flare, and (iii) investigating the change of density sensitive lines during flares using high-resolution X-ray spectra, (i) It is known that flare emission in different wavebands often correlate in time. However, here is the first time where data is presented which shows a correlation between emission from two different wavebands (soft X-rays and ultraviolet) over various sized flares and from five stars, which supports that the flare process is governed by common physical parameters scaling over a large range. (ii) As it is impossible to spatially resolve any but a very few giant stars, the only information on spatial dimensions as well as the magnetic field strength of stellar coronae has to come from indirect measurements. Using wavelet analysis, I isolated the first stellar X-ray flare oscillation. Interpreting it as a standing coronal flare loop oscillation, I derived a flare loop length as well as the magnetic field strength for this X-ray flare. (iii) The high-resolution soft X-ray spectra of Chandra and XMM-Newton allow us to determine temperatures, densities and abundances of the stellar coronae. De spite a low signal-to-noise ratio because of the relatively short duration of a flare, we find that, if adding up the photons of several flares, certain density sensitive spectral lines change significantly between quiescent and flaring states. This project led on to investigate the flaring spectrum further, and it is found that the plasma is no longer in collisional ionisation equilibrium, but that it is dominated by recombinations.

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Bonzini, Margherita. "The sub-mJy radio population in the Extended Chandra Deep Field South." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-173655.

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Deep radio observations provide a dust unbiased view of both black hole (BH) and star formation (SF) activity and therefore represent a powerful tool to investigate their evolution and their possible mutual influence across cosmic time. Radio astronomy is therefore becoming increasingly important for galaxy evolution studies thanks also to the many new radio facilities under construction or being planned. To maximise the potentiality of these new instruments it is crucial to make predictions on what they will observe and to see how best to complement the radio data with multi-wavelength information. These are the motivations of my Thesis in which I studied a sample of 900 sources detected in one of the deepest radio surveys ever made. The observations have been performed at 1.4 GHz with the Very Large Array on the Extended Chandra Deep Field South. I developed a multi-wavelength method to identify the optical-infrared counterparts of the radio sources and to classify them as radio-loud active galactic nuclei (RL AGNs), radio-quiet (RQ) AGNs, and star forming galaxies (SFGs). I was able for the first time to quantify the relative contribution of these different classes of sources down to a radio flux density limit of ∼30 μJy. I characterized the host galaxy properties (stellar masses, optical colors, and morphology) of the radio sources; RQ AGN hosts and SFGs have similar properties with disk morphology and blue colors while radio-loud AGN hosts are more massive, redder and mostly ellipticals. This suggests that the RQ and RL activity occurs at two different evolutionary stages of the BH-host galaxy co-evolution. The RQ phase occurs at earlier times when the galaxy is still gas rich and actively forming stars while the radio activity of the BH appears when the galaxy has already formed the bulk of its stellar population, the gas supply is lower, and the SF is considerably reduced. I quantified the star formation rate (SFR) of the radio sources using two independent tracers, the radio and far-infrared luminosities. I found evidence that the main contribution to the radio emission of RQ AGNs is the SF activity in their host galaxy. This result demonstrates the remarkable possibility of using the radio band to estimate the SFR even in the hosts of bright RQ AGNs where the optical-to-mid-infrared emission can be dominated by the AGN. I have shown that deep radio surveys can be used to study the cosmic star formation history; I estimated the contribution of the so-called ”starburst” mode to the total SFR density and quantified the AGN occurrence in galaxies with different levels of SF.
Tiefe Beobachtungen im Radiobereich ermöglichen einen Blick auf aktive schwarze Löcher (”black holes“, BH) und auch Gebiete aktiver Sternentstehung (”star formation“, SF), ohne dass die Beobachtungen durch den Staub in Galaxien beeinflusst werden. Daher sind Radiobeobachtungen ideal, um deren Entwicklung und eine mögliche gegenseitige Beeinflussung von BH und SF Aktivit¨at über kosmische Zeiten hinweg zu untersuchen. Radioastronomie gewinnt darum für die Erforschung von Galaxienentwicklung zunehmend an Bedeutung. Dies ist auch bedingt durch die zahlreichen neuen Radioanlagen, die im Bau oder in Planung sind. Um das Potential dieser neuen Instrumente zu maximieren, ist es essentiell Vorhersagen dar¨uber zu machen, was wir beobachten werden und zu erfahren, wie wir die Radiodaten am besten mit Multiwellenl¨angendaten ergänzen. Das ist die Motivation meiner Doktorarbeit, in der ich eine Auswahl von 900 Radioquellen untersucht habe, die in einer der tiefsten jemals durchgef¨uhrten Radiodurchmusterungen detektiert wurden. Die Beobachtungen wurden bei 1.4GHz mit dem Very Large Array auf dem ”Extended Chandra Deep Field South“durchgeführt. Ich habe eine Multiwellenl¨angenmethode entwickelt, um die optischen und infraroten Pendants dieser Radioquellen zu identifizieren und sie als radiolaute (”radio loud“, RL) aktive galaktische Kerne (”active galactic nuclei“, AGNs), radioleise (”radio quiet“, RQ) AGNs und Galaxien mit aktiver Sternentstehung (”star forming galaxies“,SFGs) zu klassifizieren. Als erste war es mir möglich, die jeweiligen Anteile dieser verschiedenen Klassen an Quellen bis zu einer Flussdichte von nur ∼30 μJy zu bestimmen. Ich charakterisierte die Galaxieneigenschaften (Sternmasse, optische Farben, Morphologie) der Radioquellen; RQ AGN Galaxien und SFGs sind ¨ahnlich bezüglich der Scheibenmorphologie und der blauen Farben, w¨ahrend RL AGN Galaxien massiver, röter und meist elliptisch sind. Dies legt nahe, dass RQ und RL Aktivität auf zwei verschiedenen Entwicklungsstufen der BH − Galaxien Koevolution stattfindet. Die RQ Phase findet früher statt, wenn die Galaxie noch gasreich ist und aktiv Sterne bildet, während BHs erst als Radioquelle aktiv werden, wenn die Galaxie bereits den Groteil ihrer Sternpopulation gebildet hat, der Gasvorrat gesunken ist und die SF erheblich zurückgegangen ist. Ich quantifizierte die Sternentstehungsrate (”star formation rate“, SFR) der Radioquellen durch zwei unabh¨angige Indikatoren, die Radio- und die Ferninfrarotleuchtkraft. Ich habe Belege gefunden, dass der Hauptanteil der Radioemission von RQ AGNs durch die SF Aktivität der Galaxie entsteht. Dieses Ergebnis eröffnet die bemerkenswerte Möglichkeit, den Radiobereich des Spektrums zu benutzen um die SFR auch in Galaxien mit hellen,RQ AGNs abzuschätzen, bei denen die optische bis mittlere Infrarot Emission vom AGN dominiert sein kann. Ich habe gezeigt, dass tiefe Radiodurchmusterungen benutzt werden können um die kosmische Sternentstehungsgeschichte zu erforschen; Ich habe den Anteil des sogenannten ”Starburst“-Modus an der gesamten SFR-Dichte abgeschätzt und das Vorkommen von AGNs in Galaxien mit verschiedenem Grad an SF quantifiziert.

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34

Samji, Isaac Chandra Annie Shalom [Verfasser]. "Intelligent Freeform Deformation for LED Illumination Optics / Annie Shalom Samji Isaac Chandra." Karlsruhe : KIT Scientific Publishing, 2018. http://www.ksp.kit.edu.

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35

Hunziker, Markus. "Harish-Chandra systems on a reductive Lie algebra and the Zuckerman functor /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1997. http://wwwlib.umi.com/cr/ucsd/fullcit?p9804516.

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36

Huenemoerder, David P., K. G. Gayley, Wolf-Rainer Hamann, Richard Ignace, J. S. Nichols, Lidia M. Oskinova, A. M. T. Pollock, Nobert S. Schulz, and Tomer Shenar. "Probing Wolf–Rayet Winds: Chandra/HETG X-Ray Spectra of WR 6." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/2692.

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With a deep Chandra/HETGS exposure of WR 6, we have resolved emission lines whose profiles show that the X-rays originate from a uniformly expanding spherical wind of high X-ray-continuum optical depth. The presence of strong helium-like forbidden lines places the source of X-ray emission at tens to hundreds of stellar radii from the photosphere. Variability was present in X-rays and simultaneous optical photometry, but neither were correlated with the known period of the system or with each other. An enhanced abundance of sodium revealed nuclear-processed material, a quantity related to the evolutionary state of the star. The characterization of the extent and nature of the hot plasma in WR 6 will help to pave the way to a more fundamental theoretical understanding of the winds and evolution of massive stars.

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Roy, Chowdhury Arpita. "Saratchandrer upanyaser bhashashilpo শরৎচন্দ্রের উপন্যাসের ভাষাশিল্প." Thesis, University of North Bengal, 2012. http://hdl.handle.net/123456789/1671.

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38

Joshi, Chandra P. [Verfasser]. "Kinetics and mechanism of the photocycle of photoactive yellow protein / Chandra P. Joshi." Berlin : Freie Universität Berlin, 2008. http://d-nb.info/1023049279/34.

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39

Bernhardt, Karen 1977. "The generalized Harish-Chandra homomorphism for Hecke algebras of real reductive Lie groups." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/28922.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mathematics, 2005.
Includes bibliographical references (p. 73-74).
For complex reductive Lie algebras g, the classical Harish-Chandra homomorphism allows to link irreducible finite dimensional representations of g to those of certain subalgebras l. The Casselman-Osborne theorem establishes an extension of this link to infinite dimensional irreducible representations. In this paper we present a generalized Harish-Chandra homomorphism construction for Hecke algebras, and establish the corresponding generalized Casselman-Osborne theorem. This homomorphism can be used to link representations of (g, L n K)-pairs to those of (g, L n K)-pairs, where is a certain subalgebra of g as in the classical case. Since representations of such pairs are closely related to those of the underlying Lie group G, this construction is a good first approximation to lifting the Harish-Chandra homomorphism from the Lie algebra to the Lie group level.
by Karen Bernhardt.
S.M.

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40

Ai, Yanli, Liming Dou, Xiaohui Fan, Feige Wang, Xue-Bing Wu, and Fuyan Bian. "EXPLORATORY CHANDRA OBSERVATION OF THE ULTRALUMINOUS QUASAR SDSS J010013.02+280225.8 AT REDSHIFT 6.30." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621217.

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We report exploratory Chandra observations of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.30. The quasar is clearly detected by Chandra with a possible component of extended emission. The rest-frame 2-10 keV luminosity is 9.0(+4.5)(+9.1) x 10(45) erg s(-1) with an inferred photon index of G = 3.03(-0.70)(+0.78). This quasar is X-ray bright, with an inferred X-ray-to-optical flux ratio alpha(ox) = -1.22(-0.05)(+0.07), higher than the values found in other quasars of comparable ultraviolet luminosity. The properties inferred from this exploratory observation indicate that this ultraluminous quasar might be growing with super-Eddington accretion and probably viewed with a small inclination angle. Deep X-ray observations will help to probe the plausible extended emission and better constrain the spectral features for this ultraluminous quasar.

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Marchesi, Stefano <1988&gt. "Black Hole and Galaxy Growth over Cosmic Time: the Chandra COSMOS Legacy Survey." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7240/1/marchesi_stefano_tesi.pdf.

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The study of supermassive black hole (SMBH) accretion during their phase of activity (hence becoming active galactic nuclei, AGN), and its relation to the host-galaxy growth, requires large datasets of AGN, including a significant fraction of obscured sources. X-ray data are strategic in AGN selection, because at X-ray energies the contamination from non-active galaxies is far less significant than in optical/infrared surveys, and the selection of obscured AGN, including also a fraction of heavily obscured AGN, is much more effective. In this thesis, I present the results of the Chandra COSMOS Legacy survey, a 4.6 Ms X-ray survey covering the equatorial COSMOS area. The COSMOS Legacy depth (flux limit f=2x10^(-16) erg/s/cm^(-2) in the 0.5-2 keV band) is significantly better than that of other X-ray surveys on similar area, and represents the path for surveys with future facilities, like Athena and X-ray Surveyor. The final Chandra COSMOS Legacy catalog contains 4016 point-like sources, 97% of which with redshift. 65% of the sources are optically obscured and potentially caught in the phase of main BH growth. We used the sample of 174 Chandra COSMOS Legacy at z>3 to place constraints on the BH formation scenario. We found a significant disagreement between our space density and the predictions of a physical model of AGN activation through major-merger. This suggests that in our luminosity range the BH triggering through secular accretion is likely preferred to a major-merger triggering scenario. Thanks to its large statistics, the Chandra COSMOS Legacy dataset, combined with the other multiwavelength COSMOS catalogs, will be used to answer questions related to a large number of astrophysical topics, with particular focus on the SMBH accretion in different luminosity and redshift regimes.

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Marchesi, Stefano <1988&gt. "Black Hole and Galaxy Growth over Cosmic Time: the Chandra COSMOS Legacy Survey." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7240/.

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The study of supermassive black hole (SMBH) accretion during their phase of activity (hence becoming active galactic nuclei, AGN), and its relation to the host-galaxy growth, requires large datasets of AGN, including a significant fraction of obscured sources. X-ray data are strategic in AGN selection, because at X-ray energies the contamination from non-active galaxies is far less significant than in optical/infrared surveys, and the selection of obscured AGN, including also a fraction of heavily obscured AGN, is much more effective. In this thesis, I present the results of the Chandra COSMOS Legacy survey, a 4.6 Ms X-ray survey covering the equatorial COSMOS area. The COSMOS Legacy depth (flux limit f=2x10^(-16) erg/s/cm^(-2) in the 0.5-2 keV band) is significantly better than that of other X-ray surveys on similar area, and represents the path for surveys with future facilities, like Athena and X-ray Surveyor. The final Chandra COSMOS Legacy catalog contains 4016 point-like sources, 97% of which with redshift. 65% of the sources are optically obscured and potentially caught in the phase of main BH growth. We used the sample of 174 Chandra COSMOS Legacy at z>3 to place constraints on the BH formation scenario. We found a significant disagreement between our space density and the predictions of a physical model of AGN activation through major-merger. This suggests that in our luminosity range the BH triggering through secular accretion is likely preferred to a major-merger triggering scenario. Thanks to its large statistics, the Chandra COSMOS Legacy dataset, combined with the other multiwavelength COSMOS catalogs, will be used to answer questions related to a large number of astrophysical topics, with particular focus on the SMBH accretion in different luminosity and redshift regimes.

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Saha, Dipak. "Uponyasik Ramesh Chandra Sen samaj bhabna o shilposiddhi উপন্যাসিক রমেশ চন্দ্র সেন : সমাজ ভাবনা ও শিল্পসিদ্ধি." Thesis, University of North Bengal, 2006. http://hdl.handle.net/123456789/2127.

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Bulbul, Gul Esra. "Rxte And Chandra Observations Of Galctic Microquasars Grs 1915+105 And Gro J1655-40." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607392/index.pdf.

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In this thesis, RXTE timing analysis of Galactic Microquasars GRO J1655-40 and GRS 1915+105, the Chandra and RXTE joint spectral analysis of GRS 1915+105 are presented. We have investigated quasi periodic oscillations (QPOs) in the black hole binaries GRO J1655-40 and GRS 1915+105 observed in 99 and 122 observations made by the Proportional Counter Array (PCA) on board Rossi X-Ray Timing Explorer (RXTE) in both low energy band (2-12 keV) and high energy band (13-27 keV), respectively. Four different X-ray states are seen in the combined characteristics of power spectra, light curves extracted by using All Sky Monitor (ASM) and spectra during 1996 and 2005. Timing analysis of RXTE observations of both of two black hole binaries GRO J1655-40 and GRS 1915+105 displays twin high frequency quasi periodic oscillations (QPOs) which are sometimes simultaneous in high energy band. It is also shown that the time averaged 30 ksec Chandra grating spectrum analysis and RXTE spectrum analysis of recent observation of GRS 1915+105 in the very high state are consistent with the parameters which were mentioned before. We briefly discussed our results and the models on black hole spin and mass.

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Pammi, Sathish Chandra [Verfasser], and Hans [Akademischer Betreuer] Uszkoreit. "Synthesis of listener vocalizations : towards interactive speech synthesis / Sathish Chandra Pammi. Betreuer: Hans Uszkoreit." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2012. http://d-nb.info/1051586569/34.

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46

Laird, Elise Sarah. "Chandra observations of ultra-violet selected star forming galaxies at redshift one and three." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428592.

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47

Garnica-Vigil, Eugenio. "On the classification of tempered representations for a group in the Harish-Chandra class." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/13244.

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Talluri, Bharath Chandra [Verfasser]. "Mechanistic and neural basis of choice-induced biases in decision-making / Bharath Chandra Talluri." Hamburg : Staats- und Universitätsbibliothek Hamburg Carl von Ossietzky, 2020. http://d-nb.info/1232407801/34.

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49

Colzani, Alice. "Analisi di osservazioni Chandra dell'ammasso PLCK G287.0+32.9: connessione tra proprietà termiche e non termiche." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/17080/.

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Gli ammassi di galassie sono strutture legate gravitazionalmente formate da almeno un centinaio di galassie. Nella banda X l’emissione deriva dal gas contenuto nell’ammasso stesso ed è in grado di fornire indicazioni su quali siano le condizioni termodinamiche della struttura. Un fenomeno di merger provoca cambiamenti nelle quantità termodinamiche dell’ammasso, come per esempio la temperatura. In base al valore di tale salto è possibile distinguere shock e cold front (discontinuità di contatto). Nella banda radio gli ammassi possono presentare emissione diffusa: nell’ammasso oggetto di studio di questa tesi sono presenti sia un alone che due relitti, entrambe strutture associate ad ammassi che hanno subito un merger. Il problema maggiore è spiegare come l’emissione possa estendersi su zone così ampie (slow diffusion problem). Attualmente esistono due soluzioni: una di esse prevede un processo di riaccelerazione che avviene nella zona in cui è possibile osservare l’emissione radio. Rimane comunque il problema del portare le particelle alle velocità relativistiche necessarie a spiegare l’emissione osservata. Tra le varie soluzione c’è il possibile legame con le radiosorgenti. In questo lavoro di tesi sono state studiate nuove osservazioni effettuate con il telescopio Chandra per l’ammasso PLCKG287.0. Esse permettono di comprendere meglio la dinamica dell’ammasso. L’analisi si è concentrata soprattutto sulla zona del relitto nord-ovest, il più vicino spazialmente al centro dell’ammasso. Esso è collegato tramite un filamento a una radiosorgente, che potrebbe fornire gli elettroni necessari a produrre l’emissione radio osservata. Lo scopo di questo lavoro è la ricerca di discontinuità nel profilo di brillanza, in modo da individuare possibili shock o cold front. Dopo un accurato lavoro di riduzione e analisi dei dati si è giunti a individuare la possibile presenza di un cold front nella regione nord-ovest dell’ammasso, la cui posizione coincide con il bordo dell’alone.

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Bernon, Florent. "Propriétés de l'intégrale de Cauchy Harish-Chandra pour les paires duales d'algèbres de Lie réductives." Poitiers, 2001. http://www.theses.fr/2001POIT2298.

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L'objet de ce travail s'inscrit dans le cadre de l'étude de la correspondance de Howe. Cette correspondance met en relation certaines représentations des groupes G et G' d'une paire duale réductive du groupe métaplectique. La conjecture de Howe prédit une relation entre les fronts d'onde de ces représentations. Dans le but d'étudier ce problème mais aussi de trouver une formule intégrale entre les caractères des représentations, Przebinda a défini une application appelée Chc. Elle associe à toute fonction lisse à support compact de g (l'algèbre de Lie de G) une fonction définie sur l'ouvert des éléments réguliers de g' (l'algèbre de Lie de G'). Le problème est de montrer que les fonctions obtenues ont les propriétés locales des intégrales orbitales. Dans le premier chapitre, on montre que les résultats de Przebinda permettent aisément d'obtenir que Chc est une intégrale orbitale pour les paires formées de groupes linéaires. On s'intéresse pour la suite de ce travail aux paires duales formées de groupes unitaires de même rang. Dans le chapitre 3, on montre que Chc possède les propriétés locales des intégrales orbitales pour les paires formées de groupes de rang 2. Les relations de saut sont obtenues à une constante multiplicative près qui ne dépend que de la paire duale. Dans le chapitre 4, dans le but de généraliser les propriétés obtenues pour les petites paires, on obtient tout d'abord une décomposition des intégrales orbitales en somme de fonctions ayant moins de sauts. On montre ensuite que ces fonctions peuvent être approchées par des produits d'intégrales orbitales de rang inférieur ou égal à 2. Dans le dernier chapitre, les résultats du chapitre 4 permettent de généraliser les résultats du chapitre 3 pour les paires duales de groupes unitaires de même rang.

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Dissertations / Theses on the topic 'Chandrian'

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