Double-peaked Balmer Emission Research Articles

HIGH-RESOLUTION SPECTROSCOPY OF THE B[e] STAR MWC 645

Optical high-resolution spectroscopic observations of the emission-line star MWC645 are presented. The spectrum exhibits strong variable double-peaked Balmer emission lines as well as low-excitation emission lines of FeII, [FeII], and [OI] which are signatures of the B[e] phenomenon, while lines of helium have not been found. In addition to the emission lines, for the first time we identified absorption lines of neutral metals (e.g., LiI 6708 A, CaI 6717 A, and a number of FeI and TiI lines) that indicate the presence of a cool component in the system. The heliocentric radial velocity measured in our best spectrum was found to be −65.1±1.0 kms −1 for the emission lines and −23.2±0.4 kms −1 for the absorption lines. Using a combination of photometric and spectroscopic data as well as the Gaia EDR3 distance (D=6.5±0.9 kpc), we disentangled the component contributions and estimated their temperatures and luminosities (∼15000 K and ∼4000 K, log L/L ? = 3.8±0.2 and 2.8±0.2 for the hot and cool component, respectively).

Double-peaked Balmer Emission Indicating Prompt Accretion Disk Formation in an X-Ray Faint Tidal Disruption Event

Abstract We present the multiwavelength analysis of the tidal disruption event (TDE) AT 2018hyz (ASASSN-18zj). From follow-up optical spectroscopy, we detect the first unambiguous case of resolved double-peaked Balmer emission in a TDE. The distinct line profile can be well-modeled by a low eccentricity (e ≈ 0.1) accretion disk extending out to ∼100 R p and a Gaussian component originating from non-disk clouds, though a bipolar outflow origin cannot be completely ruled out. Our analysis indicates that in AT 2018hyz, disk formation took place promptly after the most-bound debris returned to pericenter, which we estimate to be roughly tens of days before the first detection. Redistribution of angular momentum and mass transport, possibly through shocks, must occur on the observed timescale of about a month to create the large Hα-emitting disk that comprises ≲5% of the initial stellar mass. With these new insights from AT 2018hyz, we infer that circularization is efficient in at least some, if not all optically bright, X-ray faint TDEs. In these efficiently circularized TDEs, the detection of double-peaked emission depends on the disk inclination angle and the relative strength of the disk contribution to the non-disk component, possibly explaining the diversity seen in the current sample.

Profile of and Variability in Double-Peaked Balmer Emission Lines in 3C 445

Abstract We extract the multiple-epoch Balmer-line profiles of the heavily obscured quasar 3C 445 from the spectral curves in the literature, and analyze the emission-line profiles of the Hα and Hβ lines and the profile variability in the Hα line in the large time interval of more than three decades. The profile comparison between the Hα and Hβ lines shows that both Balmer lines share the profile with the same form, while the blue system of the Hβ line is seriously weaker than that of the Hα line. Moreover, the blue system of the Hα line suddenly disappeared completely and then did not appear again, however the other two components did not exhibit significant variation in the velocity or the amplitude. These findings suggest that the blue system of 3C 445, as with SDSS J153636.22+044127.0 and its analogs, is probable the result of the shock-heated outflowing gases. The observation angle of almost edge-on which the previous studies suggested can easily produce the high-speed and high-temperature shock in the collision between the massive outflow and the inner surface of the dusty torus.

THE NEW ECLIPSING CV MASTER OTJ192328.22+612413.5—A POSSIBLE SW SEXTANTIS STAR

ABSTRACT We present optical photometry and spectroscopy of the new eclipsing cataclysmic variable MASTER OTJ192328.22+612413.5, discovered by the MASTER team. We find the orbital period to be P = 0.16764612(5) day/4.023507(1) hr. The depth of the eclipse (2.9 ± 0.1 mag) suggests that the system is nearly edge on, and modeling of the system confirms the inclination to be between 81.°3 and 83.°6. The brightness outside the eclipse varies between observations, with a change of 1.6 ± 0.1 mag. Spectroscopy reveals double-peaked Balmer emission lines. By using spectral features matching a late M-type companion, we bound the distance to be 750 ± 250 pc, depending on the companion’s spectral type. The source displays 2 mag brightness changes on timescales of days. The amplitude of these changes, along with the spectrum at the faint state, suggest that the system is possibly a dwarf nova. The lack of any high-excitation He ii lines suggests that this system is not magnetically dominated. The light curve in both quiescence and outburst resembles that of Lanning 386, implying MASTER OTJ192328.22+612413.5 is a possible cross between a dwarf nova and a SW Sextantis star.

A RADIAL VELOCITY TEST FOR SUPERMASSIVE BLACK HOLE BINARIES AS AN EXPLANATION FOR BROAD, DOUBLE-PEAKED EMISSION LINES IN ACTIVE GALACTIC NUCLEI

ABSTRACT One of the proposed explanations for the broad, double-peaked Balmer emission lines observed in the spectra of some active galactic nuclei (AGNs) is that they are associated with sub-parsec supermassive black hole (SMBH) binaries. Here, we test the binary broad-line region hypothesis through several decades of monitoring of the velocity structure of double-peaked Hα emission lines in 13 low-redshift, mostly radio-loud AGNs. This is a much larger set of objects compared to an earlier test by Eracleous et al. and we use much longer time series for the three objects studied in that paper. Although systematic changes in radial velocity can be traced in many of their lines, they are demonstrably not like those of a spectroscopic binary in a circular orbit. Any spectroscopic binary period must therefore be much longer than the span of the monitoring (assuming a circular orbit), which in turn would require black hole masses that exceed by 1–2 orders of magnitude the values obtained for these objects using techniques such as reverberation mapping and stellar velocity dispersion. Moreover, the response of the double-peaked Balmer line profiles to fluctuations of the ionizing continuum and the shape of the Lyα profiles are incompatible with an SMBH binary. The binary broad-line region hypothesis is therefore disfavored. Other processes evidently shape these line profiles and cause the long-term velocity variations of the double peaks.

CATACLYSMIC VARIABLES IN THE SUPERBLINK PROPER MOTION SURVEY

We have discovered a new high proper motion cataclysmic variable (CV) in the SUPERBLINK proper motion survey, which is sensitive to stars with proper motions greater than 40 mas/yr. This CV was selected for follow-up observations as part of a larger search for CVs selected based on proper motions and their NUV-V and V-K$_{s}$ colors. We present spectroscopic observations from the 2.4m Hiltner Telescope at MDM Observatory. The new CV's orbital period is near 96 minutes, its spectrum shows the double-peaked Balmer emission lines characteristic of quiescent dwarf novae, and its V magnitude is near 18.2. Additionally, we present a full list of known CVs in the SUPERBLINK catalog.

SHORT TIMESCALE VARIATIONS OF THE Hα DOUBLE-PEAKED PROFILE OF THE NUCLEUS OF NGC 1097

The broad (FWHM ~ 10,000 km/s) double-peaked H{\alpha} profile from the LINER/Seyfert 1 nucleus of NGC 1097 was discovered in 1991, and monitored for the following 11 years. The profile showed variations attributed to the rotation of gas in a non-axisymmetric Keplerian accretion disk, ionized by a varying radiatively inefficient accretion flow (RIAF) located in the inner parts of the disk. We present and model 11 new spectroscopic observations of the double-peaked profile taken between 2010 March and 2011 March. This series of observations was motivated by the finding that in 2010 March the flux in the double-peaked line was again strong, becoming, in 2010 December, even stronger than in the observations of a decade ago. We also discovered shorter timescale variations than in the previous observations: (1) the first, of ~7 days, is interpreted as due to "reverberation" of the variation of the ionizing source luminosity, and the timescale of 7 days as the light crossing time between the source and the accretion disk; this new timescale and its interpretation provides a distance between the emitting gas and the supermassive black hole and as such introduces a new constraint on its mass; (2) the second, of approximately 5 months, was attributed to the rotation of a spiral arm in the disk, which was found to occur on the dynamical timescale. We use two accretion disk models to fit theoretical profiles to the new data, both having non-axisymmetric emissivities produced by the presence of an one-armed spiral. Our modeling constrains the rotation period for the spiral to be approximately 18 months. This work supports our previous conclusion that the broad double-peaked Balmer emission lines in NGC 1097, and probably also in other low-luminosity active nuclei, originate from an accretion disk ionized by a central RIAF.

3C 390.3: more stable evidence that the double-peaked broad Balmer lines originate from an accretion disc near a central black hole

In this manuscript, the structure of broad emission line regions (BLRs) of well-mapping double-peaked emitter (AGN with broad double-peaked low-ionization emission lines) 3C390.3 is studied. Besides the best fitted results for double-peaked broad optical balmer lines of 3C390.3 by theoretical disk model, we try to find another way to further confirm the origination of double-peaked line from accretion disk. Based on the long-period observed spectra in optical band around 1995 collected from AGN WATCH project, the theoretical disk parameters of disk-like BLRs supposed by elliptical accretion disk model (Eracleous et al. 1995) have been well determined. Through the theoretical disk-like BLRs, characters of observed light-curves of broad double-peaked H$\alpha$ of 3C390.3 can be well reproduced based on the reverberation mapping technique. Thus the accretion disk model is preferred as one better model for BLRs of 3C390.3. Furthermore, we can find that different disk parameters should lead to some different results about size of BLRs of 3C390.3 from the one measured through observational data, which indicates the measured disk parameters are significantly valid for 3C390.3. After that, the precession of theoretical elliptical disk-like BLRs being considered, we can find that the expected line profile in 2000 by theoretical model is consistent with the observed line profile by HST around 2000. Based on the results, we can further believe that the origination of broad double-peaked balmer emission lines of 3C390.3 are from accretion disk around central black hole.

Spectral Monitoring of AGN: Preliminary Results for Ark 564 and Arp 102B

AbstractWe present preliminary results of the long-term spectral monitoring of two active galactic nuclei with different broad line shapes: Ark 564 and Arp 102B. Ark 564 is a bright nearby narrow-line Syfert 1 (NLS1) galaxy with relatively narrow permitted optical emission lines and a high Fe II/Hβ ratio, while Arp 102B is a nearby broad-line radio galaxy with broad double-peaked Balmer emission lines. The spectra of Ark 564 were observed during 11-year period (1999-2009) and the spectra of Arp 102B in the 12-year period (1998-2009), with SAO 6 m and 1 m telescopes (Russia) and the OAGH 2.1 m telescope (Cananea, Mexico).

LONG-TERM PROFILE VARIABILITY IN ACTIVE GALACTIC NUCLEUS WITH DOUBLE-PEAKED BALMER EMISSION LINES

An increasing number of Active Galactic Nuclei (AGNs) exhibit broad, double-peaked Balmer emission lines,which represent some of the best evidence for the existence of relatively large-scale accretion disks in AGNs. A set of 20 double-peaked emitters have been monitored for nearly a decade in order to observe long-term variations in the profiles of the double-peaked Balmer lines. Variations generally occur on timescales of years, and are attributed to physical changes in the accretion disk. Here we characterize the variability of a subset of seven double-peaked emitters in a model independent way. We find that variability is caused primarily by the presence of one or more discrete "lumps" of excess emission; over a timescale of a year (and sometimes less) these lumps change in amplitude and shape, but the projected velocity of these lumps changes over much longer timescales (several years). We also find that all of the objects exhibit red peaks that are stronger than the blue peak at some epochs and/or blueshifts in the overall profile, contrary to the expectations for a simple, circular accretion disk model, thus emphasizing the need for asymmetries in the accretion disk. Comparisons with two simple models, an elliptical accretion disk and a circular disk with a spiral arm, are unable to reproduce all aspects of the observed variability, although both account for some of the observed behaviors. Three of the seven objects have robust estimates of the black hole masses. For these objects the observed variability timescale is consistent with the expected precession timescale for a spiral arm, but incompatible with that of an elliptical accretion disk. We suggest that with the simple modification of allowing the spiral arm to be fragmented, many of the observed variability patterns could be reproduced.

Double-peaked emission lines as a probe of the broad-line regions of active galactic nuclei

Broad, double-peaked, Balmer emission lines are found in the optical spectra of a relatively small fraction of active galactic nuclei. They can be an extremely useful diagnostic for the structure and dynamics of the “broad-line region” (the medium that emits the broad emission lines). In general terms the rarity and shapes of their profiles provide strong constraints on universal models of the broad-line region. A series of observational tests and basic physical considerations suggest that these lines are emitted from a flat, rotating disk, very likely the outer parts of the accretion disk that fuels the black hole. In the context of models for accretion disk winds, double-peaked emission lines originate in disks with feeble winds of low optical depth. Therefore, they provide evidence that the outer accretion disk and its associated wind are the source of the broad emission lines. Within this framework, double-peaked Balmer emission lines and corresponding high-ionization lines in the near-ultraviolet allow us to study the conditions under which the winds become dense and the onset of significant outflows. Moreover, double-peaked emission lines give us a direct view of the dense material of the disk proper and allow us to study dynamical perturbations and other transient behavior though the long-term variability of their profiles.

Radiatively Inefficient Accretion Flow in the Nucleus of NGC 1097

We present a model for the accretion flow around the supermassive black hole in the LINER nucleus of NGC 1097 that fits the optical to X-ray spectral energy distribution (SED). The X-ray segment of the SED is based on observations with the Chandra X-Ray Observatory, which are reported here for the first time. The inner part of the flow is modeled as a radiatively inefficient accretion flow (RIAF), and the outer part as a standard thin disk. The value of the transition radius (r(tr) approximate to 225R(S), where R-S = 2GM/c(2)) between the RIAF and the outer thin disk was obtained from our previous fitting of the double-peaked Balmer emission line profile, which originates in the thin disk. The black hole mass was inferred from measurements of the stellar velocity dispersion in the host galaxy. When these parameters are used in the accretion flow model, the SED can be successfully reproduced, which shows that the line profile model and the accretion flow model are consistent with each other. A small remaining excess in the near-UV is accounted for by the contribution of an obscured starburst located within 9 pc from the nucleus, as we reported in an earlier paper. The radio flux is consistent with synchrotron emission of a relativistic jet modeled by means of the internal shock scenario. In an appendix we also analyze the Chandra X-ray observations of the similar to 1 kpc circumnuclear star-forming ring and of an ultraluminous compact X-ray source located outside the ring.

Black Hole Masses of Active Galaxies with Double‐peaked Balmer Emission Lines

We have obtained near-IR spectra of five AGNs that exhibit double-peaked Balmer emission lines (NGC 1097, Pictor A, PKS 0921-213, 1E 0450.30-1817, and IRAS 0236.6-3101). The stellar velocity dispersions of the host galaxies were measured from the Ca II λλ8494, 8542, 8662 absorption lines and were found to range from 140 to 200 km s-1. Using the well-known correlation between the black hole mass and the stellar velocity dispersion, the black hole masses in these galaxies were estimated to range from 4 × 107 to 1.2 × 108 M☉. We supplement the observations presented here with estimates of the black holes masses for five additional double-peaked emitters (Arp 102B, 3C 390.3, NGC 4579, NGC 4203, and M81) obtained by other authors using similar methods. Using these black hole masses, we infer the ratio of the bolometric luminosity to the Eddington luminosity, (Lbol/LEdd). We find that two objects (Pictor A and PKS 0921-213) have Lbol/LEdd ~ 0.2, whereas the other objects have Lbol/LEdd 10-2 (nearby, low-luminosity double-peaked emitters are the most extreme, with Lbol/LEdd 10-4). The physical timescales in the outer regions of the accretion disks (at r ~ 103GM/c2) in these objects were also estimated and range from a few months for the dynamical timescale to several decades for the sound crossing timescale. The profile variability in these objects is typically an order of magnitude longer than the dynamical time, but we note that variability occurring on the dynamical timescale has not been ruled out by the observations.

Long-term profile variability of double-peaked emission lines in AGNs

An increasing number of AGNs exhibit broad, double-peaked Balmer emission lines, which are thought to arise from the outer regions of the accretion disk which fuels the AGN. The line profiles are observed to vary on a characteristic timescales of 5-10 years. The variability is not a reverberation effect; it is a manifestation of physical changes in the disk. Our group has monitored a set of 20 double-peaked emitters for the past 8 years (longer for some objects). Here, we characterize the variability of the double-peaked H alpha line profiles in five objects from our sample. By experimenting with simple models, we find that disks with a single precessing spiral arm are able to reproduce many of the variability trends that are seen in the data.

The ultraviolet spectra of active galaxies with double-peaked emission lines

We present the results of UV spectroscopy of AGNs with double-peaked Balmer emission lines. In 2/3 of the objects, the far-UV resonance lines are strong, with single-peaked profiles resembling those of Seyfert galaxies. The Mg II line is the only UV line with a double-peaked profile. In the remaining objects, the far-UV resonance lines are relatively weak but still single-peaked. The latter group also displays prominent UV absorption lines, indicative of a low-ionization absorber. We interpret the difference in the profiles of the emission lines as resulting from two different regions: a dense, low-ionization accretion disk (the predominant source of the Balmer and Mg II lines), and a lower density, higher-ionization wind (the predominant source of the far-UV resonance lines). These results suggest a way of connecting the double-peaked emitters with the greater AGN population: in double-peaked emitters the accretion rate onto the black hole is low, making the wind feeble and allowing the lines from the underlying disk to shine through. This scenario also implies that in the majority of AGNs, the wind is the source of the broad emission lines.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html

Is There an Advection‐dominated Accretion Flow in Radio Galaxies with Double‐peaked Balmer Lines?

In order to examine the prediction that the broad-line radio galaxies (BLRGs) with double-peaked Balmer lines harbor an accretion disk characterized by an advection-dominated accretion flow (ADAF) in their nuclei, we investigate narrow emission-line flux ratios of the narrow-line regions which are photoionized by the nuclear continuum radiation. We compile data from the literature and confirm the pioneering work of Eracleous & Halpern that the BLRGs with the double-peaked Balmer emission exhibit larger flux ratios of both [O I]6300/[O III]5007 and [O II]3727/[O III]5007 than the BLRGs without the double-peaked Balmer emission. To examine whether or not these properties are attributed to the difference in the spectral energy distribution (SED) of the ionizing radiation between the BLRGs with and without the double-peaked Balmer emission, we perform photoionization model calculations using two types of input continuum radiation; one has the strong big blue bump which is expected for standard optically-thick accretion disks and another does not exhibit a strong big blue bump as expected for optically-thin ADAFs. We find that the data of the BLRGs with the double-peaked Balmer lines are consistent with the models adopting the SED without a strong big blue bump while the data of the BLRGs without the double-peaked emission lines are well described by the models adopting the SED with a strong big blue bump. On the other hand, the observed differences in the NLR emission is hard to be explain by the difference in the contribution of shocks. These results support the idea that the double-peaked Balmer lines arise at an outer region of an accretion disk which is illuminated by an inner, geometrically-thick ADAF.

Transient double-peaked line emission as signatures of accretion events around supermassive black holes

We discuss the recent appearance of very broad (FWZI∼2000 km s −1) double-peaked Balmer emission lines in the nuclei of the galaxies NGC 1097, Pictor A and M 81. Such profiles are rare, and only found in about 10% of broad-line radio galaxies. In the most accepted scenario, they are the signature of relativistic gas motions around a supermassive nuclear black hole. We make a parallel between the properties of the above three nuclei: while Pictor A is a radio-galaxy similar to the others where the double-peaked profile is found, NGC 1097 and M 81 are low-luminosity nuclei located in spiral hosts. The latter galaxies nevertheless share the key characteristics of more powerful radio galaxies with double-peaked lines: narrow emission-line ratios typical of LINERs, double-peaked Balmer lines which are on average twice as broad as those of typical radio loud AGN and the presence of jets. These properties suggest that low-luminosity LINERs harbor similar nuclear engines as the most luminous active galactic nuclei (AGN), only less powerful. In these less powerful AGN, it is more easy to witness individual accretion events. Here we propose that the transient double-peaked lines are due to such events producing transient accretion disks around a supermassive nuclear black hole. We discuss, in particular, the case of NGC 1097, for which we show that the double-peaked profile and its variation over a time interval of ∼ 4 years can be well reproduced by a model of an elliptical accretion ring which could have formed from the debris released by the disruption of a star by a nuclear supermassive black hole.

Measurement of an Active Galactic Nucleus Central Mass on Centiparsec Scales: Results of Long‐Term Optical Monitoring of Arp 102B

The optical spectrum of the broad-line radio galaxy Arp 102B has been monitored for more than 13 yr to investigate the nature of the source of its broad, double-peaked hydrogen Balmer emission lines. The shape of the lines varied subtly; there was an interval during which the variation in the ratio of the fluxes of the two peaks appeared to be sinusoidal, with a period of 2.16 yr and an amplitude of about 16% of the average value. The variable part of the broad Hα line is well fitted by a model in which a region of excess emission (a quiescent hot spot) within an accretion disk (fitted to the nonvarying portion of the double-peaked line) completes at least two circular orbits and eventually fades. Fits to spectra from epochs when the hot spot is not present allow determination of the disk inclination, while fits for epochs when it is present provide a measurement of the radius of the hot spot's orbit. From these data and the period of variation, we find that the mass within the hot spot's orbit is 2.2 -->+ 0.2−0.7×10 -->8 M☉, within the range of previous estimates of masses of active galactic nuclei. Because this mass is determined at a relatively small distance from the central body, it is extremely difficult to explain without assuming that a supermassive black hole lies within Arp 102B. Our collection of spectra allows us to apply several tests to models of the source of the double peaks. The ratio of Hα to Hβ flux at a given velocity displays no turning points or points of inflection at the velocity associated with the blue peak in flux; thus, this peak should not correspond to a turning point in physical conditions. This behavior is consistent with simple accretion disk and, possibly, spiral shock models but not with models that attribute the double peaks to separate broad-line regions around a binary black hole or to broad, subrelativistic jets. The lack of systematic change in the velocity of the blue peak over time provides a further constraint on binary broad-line region models; this yields a lower limit on the mass of such a binary black hole system of at least 1010 M☉. The variability properties of the double-peaked emission lines in Arp 102B therefore continue to favor an accretion disk origin over other models.

Orbital Parameters of the Candidate Black Hole Binary GRO J0422+32

We present optical observations of the black hole candidate GRO J0422+32 in quiescence. CCD imaging over a period of two nights reveals ellipsoidal variations with an amplitude of ≍0.15 mag in I and a period of 0.<SUP>d</SUP>2107±0.<SUP>d</SUP>0012. This period is consistent with periods found during the decay from outburst. The optical spectra show strong double-peaked Balmer emission lines (characteristic of emission from an accretion disk) with a separation of ∼910 km s<SUP>-1</SUP>, implying that the projected velocity of the outer edge of the accretion disk is 455±15 km s<SUP>-1</SUP>, which in turn implies a velocity semiamplitude for the secondary star of ≲400 km s<SUP>-1</SUP>. The spectra also show TiO absorption bands indicative of early M-type dwarfs. The signal-to-noise ratios in the individual spectra are too low to extract reliable velocities. However, analyzing the full data set, we find that the most probable range of values of the secondary star velocity semiamplitude is 300 ≤ K<SUB>2</SUB> ≤ 400 km s<SUP>-1</SUP>. The implied range of mass functions is then 0.5 ≤ f(M) ≤ 1.4 M<SUB>sun</SUB>. The primary mass will then be greater than 3 M<SUB>sun</SUB> if the orbital inclination is less than 59° and the secondary star mass is less than 0.5 M<SUB>sun</SUB>.

OPTICAL AND ULTRAVIOLET SPECTROSCOPY OF VW HYDRI

ABSTRACT Spectra of the SU UMa type dwarf nova VW Hydri obtained in the visual (lambda-lambda 3400-7200A) and ultraviolet (lambda-lambda 1150-3200A) spectral regions are presented. During the quiescent phase, visual spectra of VW Hydri present strong double-peaked Balmer emission lines. In addition, He I lambda 5876, Fe II lambda-lambda 4233, 5196 He I lambda 5015, Fe II lambda 5018, He I lambda 4922, Fe II lambda 4293, He II lambda 4686, and He I lambda-lambda 4471, 6678 appear in emission. The S-wave behavior of the hot spot is well defined. The amplitude of the radial velocity curve for H-alpha is 39 (±11) km/s and for H-beta is 85 (±23) km/s. From the radial velocity amplitude and the total line width we derived the primary mass in the range of 0.91 solar mass to 1.28 solar mass and the mass ratio q = M1/M2 = 4.4 to 6.4. We applied the method given by Schoembs and Vogt (1981), which is a modified version of the method described earlier by Warner (1973). We compared and discussed the fundamental physical and spectral parameters with those in the literature. In the ultraviolet region we obtained disk temperatures in the range of 14500-48000 K, using continuum fluxes. The continuum energy distributions were compared with optically thick accretion disk models. In the IUE SWP region the best-fit spectrum is of the form Flambda proportional to lambda -2.4. In this region the effective disk radius is between 0.69Rodot and 0.75Rodot. The mass accretion rate (M) was computed with a relation given by Faulkner (1971), and is about 0-10 Modot yr-1. From the P Cygni profile of the C IV doublet, terminal velocities of about 2250 km/s for a normal outburst and 2500 km/s for superoutburst were derived. Mass loss rates were derived using these velocities as about 0.8 to 6 x 10-13 Modot yr-1 for normal outbursts and about 0.8 to 7 x 10-13 Modot yr-1 for superoutburst.