J/AJ/145/157ivo://CDS.VizieR/J/AJ/145/157doi:10.26093/cds/vizier.51450157CDSJiang P.Zhou H.Ji T.Shu X.Liu W.Wang J.Dong X.Bai J.,Wang H.Wang T.2017-06-13T11:08:27Z2014-05-28T14:22:34ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frquasarsinterstellar-reddeningA fraction of the heavily reddened quasars require a reddening curve that is even steeper than that of the Small Magellanic Cloud. In this paper, we thoroughly characterize the anomalously steep reddening law in quasars via an exceptional example observed in IRAS14026+4341. By comparing the observed spectrum to the quasar composite spectrum, we derive a reddening curve in the rest-frame wavelength range of 1200-10000{AA}. It has a steep rise at wavelengths shorter than 3000{AA}, but no significant reddening at longer wavelengths. The absence of dust reddening in the optical continuum is confirmed by the normal broad-line Balmer decrement (the H{alpha}/H{beta} ratio) in IRAS14026+4341. The anomalous reddening curve can be satisfactorily reproduced with a dust model containing silicate grains in a power-law size distribution, dn(a)/da{prop.to}a^-1.4^, truncated at a maximum size of a_max_=70nm. The unusual size distribution may be caused by the destruction of large "stardust" grains by quasar activities or a different dust formation mechanism (i.e., the in situ formation of dust grains in quasar outflows). It is also possible that the analogies of the dust grains observed near the Galactic center are responsible for the steep reddening curve. In addition, we find that IRAS14026+4341 is a weak emission-line quasar (i.e., PHL1811 analogies) with heavy dust reddening and blueshifted broad absorption lines.2013AJ....145..157Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/145/157CatalogResearchIsServedByTAP VizieR generic servicerelated-toV/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)J/ApJS/206/4 : SED and bolometric corrections for luminous QSOsJ/ApJS/183/17 : The SDSS DR5/XMM-Newton quasar survey (Young+, 2009)J/AJ/138/845 : BVRI observations of 235 bright quasars (Ojha+, 2009)J/MNRAS/382/412 : Catalog of SDSS-DR5/2MASS spectroscopic quasars (Ofek, 2007)J/ApJ/664/53 : UV photometry of GALEX QSO candidates (Atlee+, 2007)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/145/157https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/145/157http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/145/157https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/145/157https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/145/157http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/145/157GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/145/157/table3Reddening curve for 0.1<{lambda}<1{mu}mrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintsigma[1/9.7] Inverse wavelength {sigma}=1/{lambda}um**-1em.wlfloatE[0/5.5345] Reddening value at sigmamagphot.color.excessdouble