Detailed elemental abundance patterns of metal-poor ([Fe/H]∼−1 dex) stars in the Galactic bulge indicate that a number of them are consistent with globular cluster (GC) stars and may be former members of dissolved GCs. This would indicate that a few per cent of the Galactic bulge was built up from destruction and/or evaporation of globular clusters. Here an attempt is made to identify such presumptive stripped stars originating from the massive, inner Galaxy globular cluster NGC 6441 using its rich RR Lyrae variable star (RRL) population. We present radial velocities of forty RRLs centered on the globular cluster NGC 6441. All of the 13 RRLs observed within the cluster tidal radius have velocities consistent with cluster membership, with an average radial velocity of 24 ± 5 km s −1 and a star-to-star scatter of 11 km s −1 . This includes two new RRLs that were previously not associated with the cluster. Eight RRLs with radial velocities consistent with cluster membership but up to three time the distance from the tidal radius are also reported. These potential extratidal RRLs also have exceptionally long periods, which is a curious characteristic of the NGC 6441 RRL population that hosts RRLs with periods longer than seen anywhere else in the Milky Way. As expected of stripped cluster stars, most are inline with the cluster's orbit. Therefore, either the tidal radius of NGC 6441 is underestimated and/or we are seeing dissolving cluster stars stemming from NGC 6441 that are building up the old spheroidal bulge.
ABSTRACT. We present optical and infrared photometry of the unusual Type Ia supernova 2000cx. With the data of Li et al. and Jha, this constitutes the largest data set ever assembled for a Type Ia SN, more than 600 points in UBVRIJHK. We confirm the finding of Li et al. regarding the unusually blue BϪV colors as SN 2000cx entered the nebular phase. Its I-band secondary hump was extremely weak given its B-band decline rate. The V minus near-infrared colors likewise do not match loci based on other slowly declining Type Ia SNe, although VϪK is the least "abnormal." In several ways, SN 2000cx resembles other slow decliners, given its B-band decline rate [ ], the appearance of Fe iii lines and weakness of Si ii in its premaximum spectrum, Dm (B) p 0.93 15 the VϪK colors, and postmaximum VϪH colors. If the distance modulus derived from surface brightness fluctuations of the host galaxy is correct, we find that the rate of light increase prior to maximum, the characteristics of the bolometric light curve, and the implied absolute magnitude at maximum are all consistent with a subluminous object with having a higher than normal kinetic energy. Dm (B) ≈ 1.6-1.7 15
Scattering of radio waves off inhomogeneities in electron density in the interstellar medium can produce an apparent broadening in the angular diameter of an intrinsically compact background radio source. The magnitude and distribution of this effect at low galactic latitudes (|b|<5°) is not well known, although several cases suggest substantial broadening in certain directions, such as the Cygnus X region (Anderson et al. 1972), and the galactic center (Davies, Walsh, and Booth 1976). Large scattering in the plane is consistent with the scintillation properties of pulsars seen through substantial thicknesses (≳ 1 kpc) of the galactic disk.
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