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New NGC 6440 transient declining rapidly
No full textThe new transient LMXB in NGC 6440 (CXOGlb J174852.7-202124; Atel #2139) is declining rapidly. RXTE observed NGC 6440 on July 30 (18:47 to 19:26 TT). The PCA top-layer spectrum is well fit with an absorbed power-law of photon index 2.2+-0.1, with N_H set to 6e21 cm^-2 (as found by Chandra). The inferred 0.5-10 keV luminosity is 4e35 ergs/s, a decline by a factor of 3.5 from the Chandra observation ~2 days earlier
6440 Brenndolden-Auenwiesen (Cnidion dubii)
No full textDer Lebensraumtyp 6440 umfasst wechselnasse Auenwiesen aus dem Verband Deschampsion cespitosae (Synonym Cnidion dubii), die vorwiegend eine subkontinentale Verbreitung haben und gewöhnlich Brenndolde (Cnidium dubium) enthalten
Swift Confirmation of new transient activity in NGC 6440
Get PDFFollowing report of enhanced X-ray brightness from the direction of the globular cluster NGC 6440 (ATel #10821), we observed this cluster on 2017-10-05 18:52:35 UT for 1.5 ks with Swift/XRT in Photon Counting mode
DISCOVERY OF A SECOND TRANSIENT LOW-MASS X-RAY BINARY IN THE GLOBULAR CLUSTER NGC 6440
Get PDFWe have discovered a new transient low-mass X-ray binary, NGC 6440 X-2, with Chandra/ACIS, RXTE/PCA, and Swift/XRT observations of the globular cluster NGC 6440. The discovery outburst (2009 July 28-31) peaked at LX ~ 1.5 × 10[superscript 36] erg s[superscript –1] and lasted for 21, B>22 in quiescence from archival Hubble Space Telescope imaging, g'>22 during the August outburst from Gemini-South GMOS imaging, and J gsim 18.5 and K gsim 17 during the July outburst from CTIO 4 m ISPI imaging. Archival Chandra X-ray images of the core do not detect the quiescent counterpart (LX < (1-2) × 10[superscript 31] erg s[superscript –1]) and place a bolometric luminosity limit of L NS < 6 × 1031 erg s[superscript –1] (one of the lowest measured) for a hydrogen atmosphere neutron star. A short Chandra observation 10 days into quiescence found two photons at NGC 6440 X-2's position, suggesting enhanced quiescent emission at LX ~ 6 × 10[superscript 31] erg s[superscript –1]. NGC 6440 X-2 currently shows the shortest recurrence time (~31 days) of any known X-ray transient, although regular outbursts were not visible in the bulge scans before early 2009. Fast, low-luminosity transients like NGC 6440 X-2 may be easily missed by current X-ray monitoring
Internal oxygen transport in Rumex species and its significance for respiration under hypoxic conditions
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Discovery of a Second Transient Low-mass X-ray Binary in the Globular Cluster Ngc 6440
No full textWe have discovered a new transient low-mass X-ray binary, NGC 6440 X-2, with Chandra/ACIS, RXTE/PCA, and Swift/XRT observations of the globular cluster NGC 6440. The discovery outburst (2009 July 28-31) peaked at L-X similar to 1.5 x 10(36) erg s(-1) and lasted for < 4 days above L-X = 10(35) erg s(-1). Four other outbursts (2009 May 29-June 4, August 29-September 1, October 1-3, and October 28-31) have been observed with RXTE/PCA (identifying millisecond pulsations) and Swift/XRT (confirming a positional association with NGC 6440 X-2), with similar peak luminosities and decay times. Optical and infrared imaging did not detect a clear counterpart, with best limits of V > 21, B > 22 in quiescence from archival Hubble Space Telescope imaging, g' > 22 during the August outburst from Gemini-South GMOS imaging, and J greater than or similar to 18.5 and K greater than or similar to 17 during the July outburst from CTIO 4 m ISPI imaging. Archival Chandra X-ray images of the core do not detect the quiescent counterpart (L-X < (1-2) x 10(31) erg s(-1)) and place a bolometric luminosity limit of LNS < 6 x 10(31) erg s(-1) (one of the lowest measured) for a hydrogen atmosphere neutron star. A short Chandra observation 10 days into quiescence found two photons at NGC 6440 X-2's position, suggesting enhanced quiescent emission at L-X similar to 6 x 10(31) erg s(-1). NGC 6440 X-2 currently shows the shortest recurrence time (similar to 31 days) of any known X-ray transient, although regular outbursts were not visible in the bulge scans before early 2009. Fast, low-luminosity transients like NGC 6440 X-2 may be easily missed by current X-ray monitoring.Version of Recor
[Raritan River R. R., Engine Drawing Card, Sketch No. 6440]
No full textThis engine drawing card was created for the Raritan River Railroad Company, Class 10-32 1/4D. Section J-10 1/4D. Sketch 6440. Copy Spec. C-373
Eight new MSPs in NGC 6440 and NGC 6441
Get PDFWe report the discovery of five new millisecond pulsars in the globular cluster NGC 6440 and three new ones in NGC 6441; each cluster has one previously known pulsar. Four of the new pulsars are found in binary systems. One of the new pulsars, PSR J1748-2021B in NGC 6440, is notable for its eccentric (e = 0.57) and wide (Pb = 20.5 days) orbit. If the rate of advance of periastron is due solely to general relativity, we can estimate of the total mass of this binary system: 2.92 ± 0.20 solar masses. This would imply an anomalously large mass for this pulsar, which could introduce important constraints in the study of the equation of state for cold neutron matter
New outburst of the accreting-millisecond X-ray pulsar NGC 6440 X-2
No full textOn Friday 19th, 2010 (19h 13m 26s UT), the RXTE galactic bulge scans detected a flux excess in the direction of the globular cluster NGC 6440. This globular cluster is known to harbor at least 24 X-ray sources (Pooley et al. 2002, ApJ 573, 184), of which two have been identified as accreting-millisecond X-ray pulsars (AMXPs): NGC 6440 X-2 (Altamirano et al. 2010, ApJ, 712, 58) and SAX J1748.9-2021 (Altamirano et al. 2008, ApJ, 674, 45A)
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