Journal articles: 'ROSAT'

1

Cowen, Ron. "Rosat Revelations." Science News 139, no. 26 (June 29, 1991): 408. http://dx.doi.org/10.2307/3975332.

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TRÜMPER, JOACHIM E. "ROSAT: Early Results." Annals of the New York Academy of Sciences 647, no. 1 Texas/ESO-Cer (December 1991): 141–50. http://dx.doi.org/10.1111/j.1749-6632.1991.tb32165.x.

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Hasinger, Günther. "ROSAT Deep Surveys." Highlights of Astronomy 9 (1992): 199–204. http://dx.doi.org/10.1017/s1539299600008923.

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AbstractA series of 20 deep pointed observations with the ROSAT PSPC is discussed. 530 X-ray sources with 0.5-2 keV fluxes down to 3·10-15erg cm-2 s-1 have been discovered in 5.9 deg2. The N(>S) relation of the sources selected in the 0.5-2 keV band shows a density in excess of 200 deg-2 at the faintest fluxes and a flattening below 2·10-14erg cm-2 s-1. The average spectrum of those sources is a power law with energy index 1.2 ±0.1. The absorption column densities are consistent with the galactic HI columns. More than 50% of the 1-2 keV background has been resolved into discrete sources in the deepest field. The total background spectrum shows an emission line feature around 0.65 keV, most probably due to OVII-OVIII from a 2·106K plasma. Above ~ 1 keV the background is dominated by a power law spectrum with a normalization of 13.4 ± 0.2 keV cm-2 s-1 sr-1 keV-1 and a slope 1.2 ± 0.1, i.e. considerably steeper than the extrapolation from higher energies.

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Trümper, J. "The ROSAT Mission." International Astronomical Union Colloquium 115 (1990): 291–94. http://dx.doi.org/10.1017/s0252921100012483.

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AbstractThe scientific payload of ROSAT consists of a 83 cm X-ray telescope (6 – 100 Å) and a 60 cm XUV-telescope (60 – 300 Å) which are looking parallel. An important objective of the mission is to perform the first all-sky survey with imaging X-ray telescopes providing an improvement in sensitivity by several orders of magnitude compared with previous surveys. A large number of new X-ray sources (~ 105) is expected to be discovered and located with an accuracy of 1 arcmin or better, depending on source strength. The sources discovered will represent almost all types of astronomical objects, ranging from nearby normal stars to distant quasars.After completion of the sky survey which will take half a year, the instruments will be used for detailed investigations of selected sources with respect to spatial structures, spectra and time variability. In this pointing mode, which will be open for guest observers, ROSAT is expected to provide substantial improvements over the imaging instruments of the Einstein observatory.

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Hasinger, G. "ROSAT deep surveys." Advances in Space Research 13, no. 12 (December 1993): 241–51. http://dx.doi.org/10.1016/0273-1177(93)90116-s.

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6

Gottwald, Manfred, and Günther Hasinger. "Der Röntgensatellit ROSAT." Physik in unserer Zeit 21, no. 6 (1990): 258–66. http://dx.doi.org/10.1002/piuz.19900210604.

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7

Trümper, J. "Der Röntgensatellit ROSAT." Physik Journal 46, no. 5 (May 1990): 137–43. http://dx.doi.org/10.1002/phbl.19900460502.

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8

Sietmann, Richard, and Tony Jones. "Astronomy: ROSAT rolls onward." Physics World 3, no. 9 (September 1990): 7. http://dx.doi.org/10.1088/2058-7058/3/9/5.

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9

Bühler, P., T. J. L. Courvoisier, R. Staubert, H. Brunner, and G. Lamer. "ROSAT Spectra of Quasars." Symposium - International Astronomical Union 159 (1994): 369. http://dx.doi.org/10.1017/s007418090017562x.

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X–ray observations of AGN with Einstein, EXOSAT and Ginga have shown, that the spectra of quasars in the energy range 2 to 10 keV can be approximately described by a single power law model with a photon index of 1.7 to 2.0. They also suggested that a soft X-ray excess component (below ≈ 1 keV) is a common feature in many quasars. In order to investigate whether a soft excess is characteristic for a certain class of objects we analysed the data of the pointed ROSAT PSPC observations of the six radio-loud quasars PG0007+106, PKS0135-247, QSO0537-286, QSO0923+392, PG1225+317, 3C273 and the radio-quiet quasar PG0804+761. In a first step the observed spectra were fitted with an absorbed single power law model. The hydrogen column density was fixed to its galactic value and the normalisation at 1 keV and the spectral index α were the free fit parameters. In order to decide whether a soft component is present in a source, the resulting power law index was compared with the hard X-ray power law index (2–10 keV) determined in the past with other instruments. A steep ROSAT PSPC spectrum indicates the presence of an additional soft X–ray component. In four cases (PKS0135-247, PG0804+761, QSO0923+392, 3C273) we find that the spectra in the PSPC band are considerably steeper than the spectra above 2 keV and therefore suggest the presence of a soft excess. In order to quantify the contribution of the soft excess these spectra were successively fitted with a model containing a hard power law component and an additional soft component described either by a power law, thermal bremsstrahlung or black body model. For the other three members of our sample (0007+106, 0537-286, 1225+317) the fitted power law index is not enhanced. This means that no soft component has been detected, but not necessarily that it does not exist. There are two effects which render more difficult the detection of a soft component in ROSAT spectra, the absorption of photons by interstellar material and the shift of the spectra towards lower energies due to the redshift. Both processes have first an effect on the soft part of the observed spectrum and it is therefore evident, that this leads to a decrease of the sensitivity for soft X–rays of the emitted spectrum. For the three quasars in our sample, where no soft excess has been detected, either the column density (0007+106) or the redshift (0537-286, 1225+317) is especially large and therefore an eventually present soft component could have remained undetected. In these cases we calculated upper limits for the strength of such a soft component (P. Bühler et al., to be published in A&A.)

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10

Lehmann, I., G. Hasinger, M. Schmidt, R. Giacconi, J. Trümper, G. Zamorani, J. E. Gunn, et al. "The ROSAT Deep Survey." Astronomy & Astrophysics 371, no. 3 (June 2001): 833–57. http://dx.doi.org/10.1051/0004-6361:20010419.

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11

Thompson, D., L. Pozzetti, G. Hasinger, I. Lehmann, M. Schmidt, B. T. Soifer, G. Szokoly, G. Wilson, and G. Zamorani. "The ROSAT deep survey." Astronomy & Astrophysics 377, no. 3 (October 2001): 778–83. http://dx.doi.org/10.1051/0004-6361:20011049.

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12

Hasinger, G. "ROSAT/ASCA deep surveys." Nuclear Physics B - Proceedings Supplements 69, no. 1-3 (January 1999): 600–609. http://dx.doi.org/10.1016/s0920-5632(98)00303-x.

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13

Mullis, C. R., I. M. Gioia, and J. P. Henry. "The NEP ROSAT Survey." Symposium - International Astronomical Union 188 (1998): 473–74. http://dx.doi.org/10.1017/s0074180900116079.

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The Rosat All-Sky Survey (Trümper 1991, Adv. Spce Res., 2, 241) has its largest exposure times, approaching 10 ks, at the ecliptic poles where the scan circles overlap. The North Ecliptic Pole (NEP) region covers a 9° X 9° field, and contains a total of 465 X-ray sources detected at > 4σ in the 0.1-2.4 keV. We are identifying all sources in the field. The principal derivative is a statistically complete sample of galaxy clusters appropriate for more fully characterizing X-ray Luminosity Function (XLF) evolution. We report preliminary results for two subregions which are identified to the 95% level. These subregions are observed to approximately the median NEP survey exposure. They enclose 16% of the survey area and contain 96 X-ray sources representing 21% of the total NEP. The typical mix of sources is consistent with the Einstein Extended Medium Sensisitivity Survey (EMSS; Gioia et al., 1990a, ApJS, 72, 567). In particular there are 56% AGN/ELG (59% in the EMSS), 25% stars (27% in the EMSS) and 14% clusters against 13% clusters in the EMSS.

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14

Trümper, Joachim. "Astrophysik: ROSAT und seine Nachfolger: Der Forschungssatellit ROSAT hat die Röntgenastronomie revolutioniert." Physik Journal 55, no. 9 (September 1999): 45–49. http://dx.doi.org/10.1002/phbl.19990550910.

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15

Almaini, O., T. Shanks, B. J. Boyle, R. E. Griffiths, N. Roche, G. C. Stewart, and I. Georgantopoulos. "A deep ROSAT survey — XII. The X-ray spectra of faint ROSAT sources." Monthly Notices of the Royal Astronomical Society 282, no. 1 (September 1996): 295–303. http://dx.doi.org/10.1093/mnras/282.1.295.

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16

Schmitt, J. H. M. M. "Rosat Observations of Stellar Flares." International Astronomical Union Colloquium 142 (1994): 735–42. http://dx.doi.org/10.1017/s0252921100078040.

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AbstractX-ray observations of stellar flares obtained during the ROSAT all-sky survey as well as in the ROSAT pointing program are discussed. The ROSAT all-sky survey allowed—for the first time—an unbiased search for stellar flares among all types of stars. A fundamentally new result obtained is that flares can occur on all types of late-type stars, thus supporting the view that the X-ray emission from these stars is controlled by magnetic processes. Long-duration flares can be studied with the all-sky survey data particularly well, and an especially well-observed long-duration flare event on the flare star EV Lacertae is presented and discussed in detail. Finally, the issue of time variability on the shortest detectable timescales and the question of microflaring is discussed using ROSAT data from a pointed observation of UV Ceti.Subject headings: stars: coronae — stars: flare — stars: late-type — X-rays: stars

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17

Willingale, R. "ROSAT wide field camera mirrors." Applied Optics 27, no. 8 (April 15, 1988): 1423. http://dx.doi.org/10.1364/ao.27.001423.

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18

Burrows, David N., and Zhiyu Guo. "ROSAT observations of VRO 42.05.01." Astrophysical Journal 421 (January 1994): L19. http://dx.doi.org/10.1086/187177.

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19

Schmitt, J. H. M. M. "ROSAT observations of stellar flares." Astrophysical Journal Supplement Series 90 (February 1994): 735. http://dx.doi.org/10.1086/191898.

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20

Watson, Mike. "Rosat unearths X-ray secrets." Physics World 5, no. 4 (April 1992): 24–25. http://dx.doi.org/10.1088/2058-7058/5/4/25.

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21

Bickert, K. F., R. E. Stencel, and R. Luthardt. "ROSAT Observations of Symbiotic Stars." Symposium - International Astronomical Union 155 (1993): 405. http://dx.doi.org/10.1017/s0074180900171943.

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The German X-ray astronomy satellite ROSAT (launched 1990 June 1) performed an all-sky survey (from 1990 Jul 30 till 1991 Jan 26) with the Position Sensitive Proportional Counter (2 deg FoV, .1–2.4 keV) covering 96% of the sky. Analysis of bright X-ray sources suggests PSPC positions can be accurately determined to within 30 arcsec, and 1‥2 arcmin for soft weak ones. We have examined the survey data for detections from among a list of 189 symbiotic and symbiotic-like objects compiled by Vaidis (1988) with own extensions, chosen for completeness. For 178 objects, all-sky data was available. Standard Analysis Software System (SASS) and EXtended Standard Analysis Software packages (EXSAS) both use a three-step approach to detect sources. After quality screening, a sliding-window algorithm (LD) locates bright sources. These are excluded in the 2D-spline interpolated smoothed background map. A second sliding window MD runs on the background subtracted event files. All possible sources were then tested by maximum likelihood in the background-subtracted, exposure-corrected image. If LD, MD, or ML did not detected a source at the optical position, an upper limit ML program tried to find enhanced emission. For EXSAS, photon event files contain all photons within 20 arcmin radius around a source. Cut radii, background determination, and other parameters can be iteratively improved.

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22

Paronyan, Gurgen M., Hayk V. Abrahamyan, Gohar S. Harutyunyan, and Areg M. Mickaelian. "The ROSAT/NVSS AGN sample." Proceedings of the International Astronomical Union 9, S304 (October 2013): 164–65. http://dx.doi.org/10.1017/s1743921314003652.

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AbstractWe attempt to create an X-ray/radio AGN catalog and make its multiwavelength studies. ROSAT Bright Source Catalogue (BSC) contains 18,806 and ROSAT Faint Source Catalogue (FSC), 105,922 X-ray sources giving the total number of ROSAT X-ray sources 124,727 (one source is listed twice). On the other hand, NVSS radio catalogue contains 1,773,484 sources. Taking into account that X-ray sources contain AGN, bright stars and galaxies, clusters, white dwarfs (WD), cataclysmic variables (CV), etc., the cross-identification with radio catalogue may distinguish the extragalactic sources. We have cross-correlated ROSAT catalogs with NVSS one with a search radius 30 arcsec. 9,193 associations have been found. To distinguish AGN from the normal bright galaxies and clusters, Veron-Cetty & Veron AGN catalog (v.13, 2010; VCV-13) containing 168,940 objects have been used. A cross-correlation of the 9,193 ROSAT/NVSS sources with the VCV-13 with a search radius 30 arcsec resulted in 3,094 associations. Thus we are left with more 6,099 X-ray/radio sources without an optical identification. Brighter objects are normal bright galaxies, while we believe that all faint ones are candidate AGN with some contamination of distant clusters. SDSS spectroscopic survey allows us classify objects by activity types, and a number of our candidate AGN is found to be present in SDSS. We attempt to find connections between the fluxes in different wavelength ranges, which will allow us to confirm AGN and blazars candidates and in some cases find new ones.

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23

Vogler, Andreas, and Wolfgang Pietsch. "ROSAT Observations of NGC 4258." International Astronomical Union Colloquium 166 (1997): 547–50. http://dx.doi.org/10.1017/s025292110007158x.

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AbstractWe performed deep follow up observations of the active spiral galaxy NGC 4258 with the ROSAT HRI and PSPC to study the different emission components. The overall luminosity of NGC 4258 is Lx ~ 2 × 1040 erg s−1 in the 0.1 – 2.4 keV ROSAT band. Besides a weak nuclear point source (Lx ≲ 1038 erg s−1) fourteen point sources are detected in the NGC 4258 disk (integral Lx ~ 3 × 1039 erg s− 1). The bulk of the X-ray emission is not resolved. The main contributions are explained by hot interstellar medium along the anomalous spiral arms of NGC 4258 (Lx ~ 1 × 1040, T ~ 0.4 keV) and by interstellar medium escaping from NGC 4258 disk into the approaching halo hemisphere (Lx ~ 4 × 1039 erg s−1, T ~ 0.2 keV)Surface brightness, temperature and absorption profiles have been taken for the X-rays in the regions of the anomalous arms. The highest and lowest absorption was received for the NW and SE tips of the arms, respectively. Our X-ray findings are compared to a model of the anomalous arms which suggests that the bar of the galaxy causes shocks in the interstellar medium and might heat a small part of it to X-ray temperatures.

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24

Zimmermann, H. U. "ROSAT observations of recent supernovae." Astrophysics and Space Science 228, no. 1-2 (June 1995): 331–47. http://dx.doi.org/10.1007/bf00984987.

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25

Couic-Marinier, Françoise, and Dominique Laurain-Mattar. "Huile essentielle de Géranium rosat." Actualités Pharmaceutiques 57, no. 581 (December 2018): 57–59. http://dx.doi.org/10.1016/j.actpha.2018.10.012.

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26

Kürster, Martin. "Time Variability Studies with ROSAT." International Astronomical Union Colloquium 151 (1995): 423–30. http://dx.doi.org/10.1017/s0252921100035508.

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AbstractAn overview over the mission of the X-ray astronomy satellite ROSAT (Röntgensatellit) is given with an emphasis on the first soft X-ray all-sky survey carried out with an imaging telescope. Several examples of time variability studies made possible by the all-sky survey are shown for active late-type stars. Two exceptional long-duration stellar flares are presented.

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27

Ögelman, H. "Rosat observations of single pulsars." Advances in Space Research 13, no. 12 (December 1993): 135–37. http://dx.doi.org/10.1016/0273-1177(93)90105-k.

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28

Pietsch, W., and J. Trümper. "ROSAT observations of nearby galaxies." Advances in Space Research 13, no. 12 (December 1993): 171–80. http://dx.doi.org/10.1016/0273-1177(93)90109-o.

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29

Voges, W. "The ROSAT all-sky survey." Advances in Space Research 13, no. 12 (December 1993): 391–97. http://dx.doi.org/10.1016/0273-1177(93)90147-4.

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30

BECKER, WERNER. "ROSAT Observations of Neutron Stars." Annals of the New York Academy of Sciences 759, no. 1 (September 1995): 250–56. http://dx.doi.org/10.1111/j.1749-6632.1995.tb17538.x.

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31

Waldrop, M. M. "The Cosmic Eye of Rosat." Science 251, no. 4992 (January 25, 1991): 380–81. http://dx.doi.org/10.1126/science.251.4992.380.

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32

Pietsch, W. "ROSAT observations of spiral galaxies." Advances in Space Research 16, no. 3 (January 1995): 155–58. http://dx.doi.org/10.1016/0273-1177(95)00066-n.

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33

McHardy, I. M., M. R. Merrified, A. M. Newsam, L. R. Jones, D. J. Allan, T. J. Ponman, K. O. Mason, et al. "The UK ROSAT Deep Survey." Astronomische Nachrichten: News in Astronomy and Astrophysics 319, no. 1-2 (1998): 51–54. http://dx.doi.org/10.1002/asna.2123190124.

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34

Kitayama, Tetsu, Shin Sasaki, and Yasushi Suto. "Number Counts of Clusters of Galaxies in X-ray and Submm Bands." Symposium - International Astronomical Union 183 (1999): 255. http://dx.doi.org/10.1017/s0074180900132723.

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We compute the number counts of clusters of galaxies, the logN-logS relation, in several X-ray and submm bands on the basis of the Press—Schechter theory (Kitayama et al. 1998). We pay particular attention to a set of theoretical models which well reproduce the ROSAT 0.5–2 keV band logN-logS (Ebeling et al. 1997; Rosati et al. 1997), and explore possibilities to further constrain the models from future observations with ASCA and/or at submm bands. The latter is closely related to the European PLANCK mission and the Japanese LMSA project. We exhibit that one can break the degeneracy in an acceptable parameter region on the Ω0–σ8 plane by combining the ROSAT logN-logS and the submm number counts. Models which reproduce the ROSAT band logN-logS will have N(> S) ∼ (150–300)(S/10−12 erg cm−2 s−) −1.3 str−1 at S ≳ 10−12 erg cm−2 s−1 in the ASCA 2–10 keV band, and N(> Sv) ∼ (102–104)(Sv/100 mJy)−1.5 str−1 at Sv ≳ 100m J y in the submm (0.85mm) band. The amplitude of the logN-logS is very sensitive to the model parameters in the submm band. We also compute the redshift evolution of the cluster number counts and compare with that of the X-ray brightest Abell-type clusters (Ebeling et al. 1996). The results, although still preliminary, point to low density (Ω0 ∼ 0.3) universes. The contribution of clusters to the X-ray and submm background radiations is shown to be insignificant in any model compatible with the ROSAT logN-logS.

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35

Supper, R., G. Hasinger, W. H. G. Lewin, E. A. Magnier, J. van Paradijs, W. Pietsch, A. M. Read, and J. Trümper. "The second ROSAT PSPC survey of M 31 and the complete ROSAT PSPC source list." Astronomy & Astrophysics 373, no. 1 (July 2001): 63–99. http://dx.doi.org/10.1051/0004-6361:20010495.

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36

Nandra, K., A. C. Fabian, I. M. George, G. Branduardi-Raymont, A. Lawrence, K. O. Mason, I. M. McHardy, et al. "A ROSAT observation of NGC 5548." Monthly Notices of the Royal Astronomical Society 260, no. 3 (February 1, 1993): 504–12. http://dx.doi.org/10.1093/mnras/260.3.504.

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37

Crawford, C. S., and A. C. Fabian. "ROSAT observations of 3CR radio galaxies." Monthly Notices of the Royal Astronomical Society 273, no. 3 (April 1995): 827–36. http://dx.doi.org/10.1093/mnras/273.3.827.

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38

Waite, J. H., F. Bagenal, F. Seward, C. Na, G. R. Gladstone, T. E. Cravens, K. C. Hurley, J. T. Clarke, R. Elsner, and S. A. Stern. "ROSAT observations of the Jupiter aurora." Journal of Geophysical Research 99, A8 (1994): 14799. http://dx.doi.org/10.1029/94ja01005.

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Rappaport, S., D. Dewey, A. Levine, and L. Macri. "ROSAT Observations of Nine Globular Clusters." Astrophysical Journal 423 (March 1994): 633. http://dx.doi.org/10.1086/173841.

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40

Dow, K. L., and S. D. M. White. "ROSAT observations of Coma Cluster galaxies." Astrophysical Journal 439 (January 1995): 113. http://dx.doi.org/10.1086/175156.

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Plionis, M., and I. Georgantopoulos. "The ROSAT X-ray background dipole." Monthly Notices of the Royal Astronomical Society 306, no. 1 (June 11, 1999): 112–16. http://dx.doi.org/10.1046/j.1365-8711.1999.02519.x.

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42

Welty, Alan D., and Lawrence W. Ramsey. "ROSAT observations of FK comae berenices." Astronomical Journal 108 (July 1994): 299. http://dx.doi.org/10.1086/117069.

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Mickaelian, A. M., L. R. Hovhannisyan, D. Engels, H. J. Hagen, and W. Voges. "Optical identification of ROSAT-FSC sources." Astronomy & Astrophysics 449, no. 1 (March 16, 2006): 425–33. http://dx.doi.org/10.1051/0004-6361:20053967.

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44

Danner, R., S. R. Kulkarni, and S. E. Thorsett. "ROSAT observations of six millisecond pulsars." Astrophysical Journal 436 (December 1994): L153. http://dx.doi.org/10.1086/187655.

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Nicholson, K. L., J. P. D. Mittaz, and K. O. Mason. "Variability of faint ROSAT field sources." Monthly Notices of the Royal Astronomical Society 285, no. 4 (March 11, 1997): 831–38. http://dx.doi.org/10.1093/mnras/285.4.831.

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46

Barstow, Martin A. "XUV wide field camera for ROSAT." Optical Engineering 29, no. 6 (1990): 649. http://dx.doi.org/10.1117/12.55637.

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47

Brinkmann, W. "ROSAT Observations of Active Galactic Nuclei." Symposium - International Astronomical Union 159 (1994): 53–62. http://dx.doi.org/10.1017/s0074180900174844.

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The large number of Active Galactive Nuclei detected for the first time through their X-ray emission in the ROSAT All Sky Survey as well as the first measurements of the X-ray emission of many previously known AGN provide a new unprecedented large basis for the statistical and morphological exploration of these objects.The soft energy range of the X-Ray Telescope, the good energy resolution of the PSPC detector, and the high sensitivity of the instrument further allows an investigation of the spectral properties of sources in this energetically important energy band.A short overview is given of the actual ongoing research concentrating on the study of the soft X-ray class properties of the various types of AGN.

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48

Cappi, M., G. G. C. Palumbo, R. Della Ceca, and T. Maccacaro. "ROSAT Observations of Einstein EMSS AGNs." Symposium - International Astronomical Union 159 (1994): 370. http://dx.doi.org/10.1017/s0074180900175631.

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Active Galactic Nuclei (AGN) can be studied in the ROSAT energy band also when serendipitously observed during long pointed observation of unrelated targets. From the available ROSAT database three Extended Medium Sensitivity Survey (EMSS) AGNs, detected with more than 500 counts, have been studied. One AGN (MS 1803.6+6738 = Kaz 102) was observed twice and in one field the target is the BL Lac 0716+714.– Spectral studies reveal that all three AGNs are well described by a single power law. Values of relevance are summarized in the table where they are compared to previous values from Einstein and the ROSAT survey (Walter R. & Fink H.H., 1993, A&A, 274, 105). All four sources have a NH value well below the estimated value given by Stark et al. (1992, ApJS, 79, 77) and Elvis et al. (1989, ApJ, 97, 777). This probably is an indication that a soft excess is present.– Variability studies show flux variations for the BL Lac on time scales of days, while the photon index appears rather constant. The high count rate for this object allows to attribute a probability of variability greater than 99% (running a K-S test against constancy). In the case of Kaz 102, the comparison of previous measurements with the present one does not show evidence of long term (years) variability.

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49

Brinkmann, W., J. Siebert, and W. Yuan. "ROSAT Studies of Extragalactic Radio Sources." Symposium - International Astronomical Union 175 (1996): 259–62. http://dx.doi.org/10.1017/s0074180900080736.

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Complementary information over a large energy range appears to be the best way to study the class properties of Active Galactic Nuclei (AGN). While radio data provide superior spatial resolution required for the analysis of source structures and their morphology, optical data are a necessary ingredient for the classification of the objects and for the determination of their redshifts. Finally, X-ray (and more recently γ-ray) observations give vital information about the energetics of the central engines and on the physical conditions of the ‘heart of the machine’.

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50

SELTZER, RICHARD. "Hubble, ROSAT yield dramatic space photos." Chemical & Engineering News 68, no. 43 (October 22, 1990): 29. http://dx.doi.org/10.1021/cen-v068n043.p029.

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Journal articles on the topic 'ROSAT'

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