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Dissertations / Theses on the topic 'Variable stars'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 July 2025

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1

Davey, Stephen. "Irradiation of the secondary star in cataclysmic variable stars." Thesis, University of Sussex, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386388.

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2

Kube, Jens. "Indirect imaging of cataclysmic variable stars." Doctoral thesis, [S.l.] : [s.n.], 2002. http://webdoc.sub.gwdg.de/diss/2002/kube/kube.pdf.

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3

Thoroughgood, Timothy David. "The masses of cataclysmic variable stars." Thesis, University of Sheffield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419603.

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4

Marsh, T. R. "Emission lines in cataclysmic variable stars." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372891.

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5

Sahman, David. "The evolution of cataclysmic variable stars." Thesis, University of Sheffield, 2018. http://etheses.whiterose.ac.uk/21700/.

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Cataclysmic variables (CVs) are binary star systems comprising a white dwarf which is accreting material from a Roche-lobe filling companion, usually a late-main sequence or evolved star. The accreted material accumulates on the surface of the white dwarf and ultimately leads to a thermonuclear runaway explosion, called a nova eruption. There are ∼ 400 recorded novae and some have shown more than one eruption. These systems are the recurrent novae, and they are one of the leading progenitor candidates of Type Ia Supernovae. In this thesis, I describe how I used high speed spectroscopy to deter

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6

Wynn, Graham Anthony. "Accretion processes in cataclysmic variable stars." Thesis, University of Leicester, 1993. http://hdl.handle.net/2381/35833.

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7

Pretorius, Magaretha L. "Rapid oscillations in cataclysmic variable stars." Master's thesis, University of Cape Town, 2004. http://hdl.handle.net/11427/6103.

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Includes bibliographical references (p. 129-146).<br>Rapid quasi-coherent oscillations were detected in the optical light curves of 24 cataclysmic variable stars (CVS). In 12 of these systems (TU Men, WW Cet, HX Peg, BP CrA, BR Lup, HP Nor, AG Hya, TW Vir, PU CMa, V426 Ooph, V1193 Ori, and CR Boo) for the first time. The results contribute to the observational record of the phenomenology of dwarf nova oscillations (DNOs), quasi-periodic oscillations (QPOs), and longer period dwarf nova oscillations (lpDNOs), strengthen the correlation, valid over nearly six orders of magnitude in frequency, be

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8

Ireland, Michael. "Optical interferometry and Mira variable stars /." Connect to full text, 2005. http://hdl.handle.net/2123/721.

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9

Ireland, Michael James. "Optical Interferometry and Mira Variable Stars." Thesis, The University of Sydney, 2005. http://hdl.handle.net/2123/721.

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This thesis describes the development of a red tip/tilt and fringe detection system at the Sydney University Stellar Interferometer (SUSI), modelling the instrumental performance and effects of seeing at SUSI, making observations of Mira variable stars and finally modelling the atmospheres of Mira variables with physically self-consistent models. The new SUSI tip/tilt system is based around a CCD detector and has been successfully used to both track the majority of tip/tilt power in median seeing at an R magnitude of 4.5, and to provide seeing measures for post processing. The new fringe-det

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10

Ireland, Michael James. "Optical Interferometry and Mira Variable Stars." University of Sydney. Physics, 2005. http://hdl.handle.net/2123/721.

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This thesis describes the development of a red tip/tilt and fringe detection system at the Sydney University Stellar Interferometer (SUSI), modelling the instrumental performance and effects of seeing at SUSI, making observations of Mira variable stars and finally modelling the atmospheres of Mira variables with physically self-consistent models. The new SUSI tip/tilt system is based around a CCD detector and has been successfully used to both track the majority of tip/tilt power in median seeing at an R magnitude of 4.5, and to provide seeing measures for post processing. The new fringe-det

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11

Todd, I. G. "Variable stars as distance indicators in M31." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492481.

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The distance scale in the universe is of key importance. To detennine the distance to objects far out in the universe, reliable distance indicators, or standard candles must be found and reliably characterised. This study focussed on the detection of cepheids and eclipsing binaries in the Andromeda Galaxy (M31) using the relatively new method of Difference Imaging Analysis (DIA), deemed to yield better results in crowded fields. Many eclipsing binaries and cepheids were found. Due the lack of spectroscopy, the calculation of distance using EBs was not possible, however accurate locations and p

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12

Wynn, Rebecca. "Accretion disc instabilities in cataclysmic variable stars." Thesis, University of Leicester, 2000. http://hdl.handle.net/2381/30642.

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A 1D hydrodynamical code is used to model the viscous evolution of VY Scl stars, which are a subclass of Cataclysmic Variable. Low states arise as a result of occasional drops in the mass transfer rate, which probably result from the passage of starspots across the inner Lagrangian point on the secondary star. The model includes the heating of the accretion disc by irradiation from the white dwarf and shows that outbursts from the low state can be suppressed if the temperature of the white dwarf is sufficiently high (Twd 40 000 K). A magnetic propeller model is used to show that the quiescent

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13

Hickman, Richard D. G. "Multi-wavelength observations of cataclysmic variable stars." Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/38153/.

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Observations of the cataclysmic variable systems EX Dra, Z Cha, and OY Car using multi-wavelength data ranging from near-infrared to X-ray bands are presented and analysed. Obscuration of the white dwarf by intervening material is discussed in context of all three systems, including the confirmation of iron lines in the spectrum of OY Car and the absorbing nature of the accretion disc upon the soft X-ray band in Z Cha. Evidence for spiral shocks and slingshot prominences from the secondary star are found in EX Dra, while the extent of Z Cha's boundary layer is probed with extensive modelling o

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14

Smith, Deneal Anthony. "An observational study of cataclysmic variable stars." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624581.

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15

Greenwood, Aaron James. "Spectroscopic Analysis of γ Doradus Variable Stars". Thesis, University of Canterbury. Physics and Astronomy, 2014. http://hdl.handle.net/10092/9216.

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Three γ Doradus-type stars are analysed: HD139095, HD153580, and HD197541. Long-term observation campaigns have been conducted on each star, with over 300 spectra of each star being gathered for analysis using the HERCULES spectrograph at Mount John University Observatory. For each star, cross-correlation techniques were used to obtain representative line profiles for each spectrum. The analysis of these line profiles has resulted in frequency and pulsation mode identifications for these three stars. Abundance analysis has also been performed on HD139095 and HD197541, and their fundamental par

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16

Feline, William James. "ULTRACAM photometry of eclipsing cataclysmic variable stars." Thesis, University of Sheffield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.425598.

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17

Baskill, Darren Stuart. "X-ray properties of cataclysmic variable stars." Thesis, University of Leicester, 2003. http://hdl.handle.net/2381/30669.

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In this thesis, I study the entire sample of non-magnetic cataclysmic variables observed with the Japanese satellite ASCA, presenting a detailed analysis of the spectral and temporal behaviour of these twenty-nine targets. The spectral analysis indicates that all the targets in the ASCA sample appear to be X-ray under-luminous, with only three possible exceptions. This indicates that energy is being lost from the accretion disk in a non-radiative way. Since a third of the observations require additional absorption above that expected from interstellar alone, both the X-ray under-luminosity and

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18

Romero, Daniela. "Comparing the Period-Luminosityrelationships in variable stars." Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-323634.

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There are four Period Luminosity relations from three sources, [3, 5, 9, 11], that are compared for theiraccuracy in calculating distances and to see how much uncertainty has to be considered when calculatingother distances based on these. Here, the relations are compared by using each to calculate and compare thedistances of the stars: BK Vir, L2 Pup, R Hor, R Hya, R Lep, and RR Aql; along with using data from AAVSOand SIMBAD in the calculations. The relations have an uncertainty that ranges from about 30%-40%, exceptfor the relation from [9] that has an uncertainty of 90%

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19

Hodder, Philip Jeremy Crichton. "A search for faint variable stars in the globular cluster M71." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28830.

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A 67" x 104" area of the metal-rich globular cluster M71 was searched for variable stars using 73 CCD frames. Using mean B and V values a colour-magnitude diagram down to V ≈ 22 is constructed. Four variables were discovered, with two more stars classed as possible candidates for variability. Phase diagrams and real time light curves are presented for all variables. One variable blue straggler (or SX Phe star) has been discovered with a period of 0.d05181. Values for the mass depend on the pulsation mode assumed for this star - (0.90 ± 0.13)M. for the first overtone mode, and (1.57 ± 0.22)M. f

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20

Barker, John. "Driving mechanisms for cataclysmic variable evolution." Thesis, Open University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289006.

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21

Papakonstantinou, Nikolaos. "Investigation of variable Ap Stars in TESS continuous viewing zone." Thesis, Uppsala universitet, Observationell astrofysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-441349.

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22

Dunlap, Mickey Paul. "Using the bootstrap to analyze variable stars data." Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/1398.

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Often in statistics it is of interest to investigate whether or not a trend is signiﬁcant. Methods for testing such a trend depend on the assumptions of the error terms such as whether the distribution is known and also if the error terms are independent. Likelihood ratio tests may be used if the distribution is known but in some instances one may not want to make such assumptions. In a time series, these errors will not always be independent. In this case, the error terms are often modelled by an autoregressive or moving average process. There are resampling techniques for testing the hypothe

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23

Weldrake, David Thomas Fredrick, and weldrake@mpia-hd mpg de. "Giant Planets and Variable Stars in Globular Clusters." The Australian National University. Research School of Astronomy and Astrophysics, 2005. http://thesis.anu.edu.au./public/adt-ANU20050616.191315.

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Over the last decade, 135 extrasolar planets have been discovered, the vast majority found by ongoing radial velocity searches. Of the stars sampled in these searches, 1% have `Hot Jupiter' planets associated with them. Having masses equivalent to Jupiter yet orbital periods of only a few days, this new class of planet is clearly unlike anything in our Solar System.¶ Hot Jupiters present us with an intriguing prospect. If the orientation of the planetary orbit is close to edge-on, the planet will periodically transit across the face of its star, resulting in a small drop in brightness. This t

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24

Thomas, Nigel Leslie. "Optical and infrared observations of cataclysmic variable stars." Thesis, Open University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497399.

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In this thesis I show how flux ratios taken between fiducial orbital phases in the light curves of irradiated CVs can be used to measure the degree of heating of the secondary star. I compare the heating effect obtained from flux ratio analysis with more formal modelling, or by measurements taken from the literature, in the classical novae QU Vul, V Per, DD Cir, DN Gem, V1432 Aql, and WY Sge. I find good agreement. I use the results to determine how irradiation changes with time since the nova outburst, and conclude that it is the decline in reprocessed irradiation from the cooling white dwarf

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25

Poole, Tracey Suzanne. "A multi-wavelength study of cataclysmic variable stars." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.415225.

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26

North, Rachel Caroline. "Probing the system parameters of cataclysmic variable stars." Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390623.

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27

Unda-Sanzana, Eduardo. "A spectroscopic analysis of three cataclysmic variable stars." Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414368.

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28

Fernley, J. A. "Optical and infrared observations of pulsating variable stars." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/35882.

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In this thesis complete light curves, at both optical (V) and infrared (J, H, K) wavelengths, are presented for 15 pulsating variable stars. These include four dwarf Cepheids, six RR Lyraes and five Cepheids. In addition, radial velocity curves are also presented for three stars. Using this data, and existing radial velocity curves taken from the literature, we derive radii for all the stars using a variant of the Baade-Wesselink method. The value of the infrared for radius determination is illustrated by the fact that no previous attempts to apply Baade-Wesselink type methods, in an empirical

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29

Brooks, A. "Short period variable stars in the Kepler field." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1447063/.

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The Kepler Satellite provides unique opportunities in stellar astrophysics, with its observations being of particular importance to the asteroseismology community. With Kepler having a limited target list due to data telemetry limitations, pre-launch time series and colour photometric surveys were undertaken to identify suitable targets for observation. However, none of these combined cadence and depth that matched that derived using Kepler itself. This meant that there were potentially many short period variable sources awaiting discovery which could be observed by Kepler. We therefore chose

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30

Weldrake, David Thomas Frederick. "Giant planets and variable stars in globular clusters /." View thesis entry in Australian Digital Theses Program, 2005. http://thesis.anu.edu.au/public/adt-ANU20050616.191315/index.html.

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31

Hoard, Donald Wayne. "Accretion and structure in the SW Sextantis stars /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/5419.

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32

Woodruff, Henry Christian A. "Optical and infrared aperture masking interferometry of mira variable stars." Thesis, The University of Sydney, 2009. https://hdl.handle.net/2123/28457.

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1.1 A Brief History of Interferometry The theoretical angular resolution of a telescope with perfect optics is proportional to the diameter of the aperture. A 10 m telescope (e.g. the Keck I telescope on Mauna Kea, Hawaii) in the visible range of light (x1 z 500 nm) could theoretically achieve resolutions of 12 milliarcseconds (mas). It might seem that in order to increase angular resolution, building bigger telescopes would be the only reasonable thing to do! In reality, the comfortable blanket of the Earth’s atmosphere has proven to be quite a show stopper for high-resolution observa

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33

Smits, Derck Peter. "Atomic processes in nova shells." Doctoral thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/16000.

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Bibliography: pages 155-165.<br>The unusual spectra of the spatially-resolved nova shells of DQ Her, T Aur and CP Pup are reviewed. Because calculations for these conditions have not been made, recombination models of HI, HeI and CNO from a neutral to a doubly ionized state were constructed. The models are described and the results presented for densities at various temperatures. A photoionization model is also described. The effects of non-uniform density distributions in nova shells have been investigated and the observational consequences discussed. A model of the CP Pup shell is described

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34

Hartley, Louise Elizabeth. "Observation and outflow modelling of luminous cataclysmic variable stars." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.407959.

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35

Pretorius, Magaretha Le Riche. "Observational constraints on the evolution of cataclysmic variable stars." Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485009.

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I provide observational constraints on the size and period distribution of the Galactic cataclysmic variable (CV) population, and derive the implications that these constraints have for the theory of CV evolution. The results are based on quantitative modelling applied to three observational CV samples, tw<? of which are newly constructed here. Large differences between the size and other properties of the known sample of CVs and the predictions of the theory of binary star evolution have long been recognized. However, because all existing observational CV samples suffer from strong selection

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36

Bass, Gideon. "Ensemble supervised and unsupervised learning with Kepler variable stars." Thesis, George Mason University, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10027479.

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<p>Variable star analysis and classification is an important task in the understanding of stellar features and processes. While historically classifications have been done manually by highly skilled experts, the recent and rapid expansion in the quantity and quality of data has demanded new techniques, most notably automatic classification through supervised machine learning. I present a study on variable stars in the Kepler field using these techniques, and the novel work of unsupervised learning. I use new methods of characterization and multiple independent classifiers to produce an ensembl

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37

Caddy, Robert V. "Time Series Photometry of the Symbiotic Star V1835 Aql and New Variable Stars in Aquila." Bowling Green State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1525438143057776.

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38

PENNING, WILLIAM ROY. "INVESTIGATIONS OF LONG-PERIOD DQ HERCULIS STARS." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/188161.

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The magnetic rotator model has long been the favored explanation for coherent photometric modulations in the DQ Herculis class of cataclysmic variables. However, to date, all evidence supporting this model has been of the indirect variety. Unlike their synchronously rotating cousins, the AM Herculis objects, DQ Herculis stars have not yet been discovered to emit polarized radiation. Therefore, in light of this crucial lack, the evidence used to place these objects in the magnetic cataclysmic variable category has been strictly circumstantial, based primarily on the coherence of the photometric

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39

Call, Scott. "Long-Period Variable Stars in the Globular Cluster NGC 6553." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1626973295690519.

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40

Drake, A. J., S. G. Djorgovski, M. Catelan, et al. "The Catalina Surveys Southern periodic variable star catalogue." OXFORD UNIV PRESS, 2017. http://hdl.handle.net/10150/625504.

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Here, we present the results from our analysis of 6 yr of optical photometry taken by the Siding Spring Survey (SSS). This completes a search for periodic variable stars within the 30 000 deg(2) of the sky covered by the Catalina Surveys. The current analysis covers 81 million sources with declinations between -20 degrees. and -75 degrees. with median magnitudes in the range 11 < V < 19.5. We find approximately 34 000 new periodic variable stars in addition to the similar to 9000 RR Lyrae that we previously discovered in SSS data. This brings the total number of periodic variables identified i

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41

Woollands, Robyn. "Photometric Analysis of R Coronae Borealis stars in the Magellanic Clouds." Thesis, University of Canterbury. Physics and Astronomy, 2008. http://hdl.handle.net/10092/1876.

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This thesis presents the initiation of a multi-site photometric programme to examine the extraordinary behaviour displayed by 18 R Coronae Borealis (RCB) stars in the Magellanic Clouds (MCs). RCB stars exhibit a unique variability whereby they undergo rapid declines of up to several magnitudes. The decline may take several weeks, whereas the recovery to maximum light may take months or even years. The accepted wisdom for the cause of these enigmatic declines is a phenomenon whereby dust formed in the stellar environment reduces the brightness by as much as eight magnitudes (Clayton 1996). This

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42

Deschamps, Romain. "Evolution of low and intermediate mass stars in binary systems: a new look at Algol systems." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209077.

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Despite being observed since the XVIIIth century, Algol systems and related objects are<p>still rather poorly understood. We know that they are composed by a generally B-A main sequence<p>star and a lighter but more evolved companion star. This paradox is explained by the transfer of mass<p>between the two stars, but new problems arose. In particular, I studied the mass-transfer driven spin-<p>up of the accreting star that drives the star to critical rotation and the puzzling, indirectly observed, non-conservative evolution.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished

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Blakelock, Carolyn J. "Time-resolved spectroscopy of the AM Herculis-type binary systems QQ VUL and EF ERI." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1115429.

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Cataclysmic variable stars (CVs) are interacting binary systems. One of the stars (referred to as the primary) is a white dwarf, the other (referred to as the secondary) is usually a late main sequence star such as a red dwarf. Due to the closeness of the two stars, the white dwarf accretes gasses from the secondary. If the white dwarf does not possess a strong magnetic field, these gasses go into orbit, forming an accretion disk around the primary. If the white dwarf does possess a strong magnetic field, the gasses cannot form an accretion disk because they are entrained by the magnetic field

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Kawka, Adela. "A study of white dwarfs in the solar neighbourhood." Thesis, Kawka, Adela (2003) A study of white dwarfs in the solar neighbourhood. PhD thesis, Murdoch University, 2003. https://researchrepository.murdoch.edu.au/id/eprint/120/.

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The aim of this thesis is to revisit the properties of white dwarf stars in the Solar neighbourhood (distance > 100 pc), in particular their magnetic fields, the occurrence of binarity and their space density. This thesis presents observations and analysis of a sample of white dwarfs from the southern hemisphere. Over 80 objects were observed spectroscopically, and 65 of these were also observed with a spectropolarimeter. Many of the white dwarfs observed belong to the Solar neighbourhood, and can be used to study the star formation and evolution in this region. Our spectropolarimetric meas

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Kawka, Adela. "A study of white dwarfs in the solar neighbourhood." Kawka, Adela (2003) A study of white dwarfs in the solar neighbourhood. PhD thesis, Murdoch University, 2003. http://researchrepository.murdoch.edu.au/120/.

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The aim of this thesis is to revisit the properties of white dwarf stars in the Solar neighbourhood (distance > 100 pc), in particular their magnetic fields, the occurrence of binarity and their space density. This thesis presents observations and analysis of a sample of white dwarfs from the southern hemisphere. Over 80 objects were observed spectroscopically, and 65 of these were also observed with a spectropolarimeter. Many of the white dwarfs observed belong to the Solar neighbourhood, and can be used to study the star formation and evolution in this region. Our spectropolarimetric meas

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Pala, A. F., B. T. Gänsicke, D. Townsley, et al. "Effective temperatures of cataclysmic-variable white dwarfs as a probe of their evolution." OXFORD UNIV PRESS, 2017. http://hdl.handle.net/10150/623936.

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We present HST spectroscopy for 45 cataclysmic variables (CVs), observed with HST/COS and HST/STIS. For 36 CVs, the white dwarf is recognisable through its broad Ly a absorption profile and we measure the white dwarf effective temperatures (T-eff) by fitting the HST data assuming log g = 8.35, which corresponds to the average mass for CV white dwarfs (similar or equal to 0.8M(circle dot)). Our results nearly double the number of CV white dwarfs with an accurate temperature measurement. We find that CVs above the period gap have, on average, higher temperatures (< T-eff > similar or equal to 23

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Friedman, Vanessa Ann. "Identifying Long Period Variable (LPV) Stars Using Images from the Stardial Observatory." Thesis, The University of Arizona, 2009. http://hdl.handle.net/10150/193423.

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The study of variable stars is extremely important to the astronomical field of scientific research. Variable stars must be methodically studied, usually by amateur astronomers over a long period of time, in order to provide professional astronomers important data that allows them to further analyze variable star behavior.Variable stars are unique because their pulsation produces visible changes in luminosity. This pulsation allows amateur astronomers to visually observe and identify variable stars. This type of research and study is special because amateurs can make a real contribution to the

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Vilardell, Sallés Francesc. "Determination of the distance to the Andromeda Galaxy using variable stars." Doctoral thesis, Universitat de Barcelona, 2009. http://hdl.handle.net/10803/751.

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The Andromeda Galaxy (M31) is an excellent distance calibrator in the Cosmological Distance Ladder. We present the first direct distance determination to M31 using eclipsing binaries (EBs). EBs provides direct distance determinations because the fundamental properties of their components can be measured without any previous calibration. Distance determination with EBs requires, at least, two data sets: time series photometry and spectroscopy.<br/>We obtained high quality light curves (rms~0.01 mag) from a 34'x34' photometric survey in M31 (in Johnson B and V filters) carried out at the 2.5 m I

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Smitka, Michael Thomas. "Analysis of the Halo Globular Cluster M30 and its Variable Stars." Bowling Green State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1182382804.

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Pellegrin, Kyle S. "Long Period Variable Stars in the Globular Cluster M5 (NGC 5904)." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1595605798891894.

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