1,733,534 research outputs found
A search for coherent radio emission from RX J0648.0-4418
No full textRX J0648.0-4418is a compact star with a spin period of 13.2 s. It is either the most rapidly rotating white dwarf known or a slowly rotating neutron star. Here, we report on the first searches for coherent pulsar-like radio emission from RX J0648.0-4418, both for sporadic bursts and steady periodic emission. No such emissionwas detected, with our limits suggesting that no such mechanism is active. We further searched our data for fast radio bursts to a dispersion measure corresponding to a redshift of ~12. We did not detect any such events
St. Louis & San Francisco (SLSF) "Frisco" 4418
No full textA photograph print showing the St. Louis and San Francisco (SLSF) "Frisco" 4418, 4-8-2, St. Louis, MO
Block Card 4418 East Way
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: Dwelling (Toledo, Ohio) | Side gabled | Homeville Subdivision (Toledo, Ohio) | Willys Park area (Toledo, Ohio) | West Toledo (Toledo, Ohio) | 4418 East Way (Toledo, Ohio) | Folk House Styl
Block Card 4418 Fir Lane
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: dwelling | 4418 Fir Lane (Toledo, Ohio) | Colonial Revival Style | box bay windows | DeVeaux (Toledo, Ohio) | Extension of Mellwood (Toledo, Ohio
Vibrationally excited HC3N in NGC 4418
No full textAims. We investigate the molecular gas properties of the deeply obscured luminous infrared galaxy NGC 4418. We address the excitation of the complex molecule HC3N to determine whether its unusually luminous emission is related to the nature of the buried nuclear source.
Methods. We use IRAM 30 m and JCMT observations of rotational and vibrational lines of HC3N to model the excitation of the molecule by means of rotational diagrams.
Results. We report the first confirmed extragalactic detection of vibrational lines of HC3N. We detect 6 different rotational transitions ranging from J = 10–9 to J = 30–29 in the ground vibrational state and obtain a tentative detection of the J = 38–37 line. We also detect 7 rotational transitions of the vibrationally excited states v6 and v7, with angular momenta ranging from J = 10–9 to 28–27. The energies of the upper states of the observed transitions range from 20 to 850 K. In the optically thin regime, we find that the rotational transitions of the vibrational ground state can be fitted for two temperatures, 30 K and 260 K, while the vibrationally excited levels can be fitted for a rotational temperature of 90 K and a vibrational temperature of 500 K. In the inner 300 pc of NGC 4418, we estimate a high HC3N abundance, of the order of 10-7.
Conclusions. The excitation of the HC3N molecule responds strongly to the intense radiation field and the presence of warm, dense gas and dust at the center of NGC 4418. The intense HC3N line emission is a result of both high abundances and excitation. The properties of the HC3N emitting gas are similar to those found for hot cores in Sgr B2, which implies that the nucleus (<300 pc) of NGC 4418 is reminiscent of a hot core. The potential presence of a compact, hot component (T = 500 K) is also discussed
VV 655 and NGC 4418: Implications of an interaction for the evolution of a LIRG
Get PDFContext. VV 655, a dwarf irregular galaxy with HI tidal debris, is a companion to the lenticular luminous infrared galaxy (LIRG) NGC 4418. NGC 4418 stands out among nearby LIRGs due to its dense central concentration of molecular gas and the dusty, bi-polar structures along its minor axis suggestive of a wind driven by a central starburst and possible nuclear activity.
Aims. We seek to understand the consequences of the ongoing minor interaction between VV 655 and NGC 4418 for the evolution of the LIRG. Specifically, we consider the origin of the gas supply responsible for the unusual nuclear properties of NGC 4418.
Methods. We investigate the structural, kinematic, and chemical properties of VV 655 and NGC 4418 by analyzing archival imaging data and optical spectroscopic observations from the SDSS-III and new spectra from SALT-RSS. We characterize their gas-phase metal abundances and spatially resolved, ionized gas kinematics to better understand whether gas transfer between VV 655 and NGC 4418 resulted in the highly obscured nucleus of the LIRG.
Results. The gas-phase metallicity in NGC 4418 significantly exceeds that in VV 655. No kinematic disturbances in the ionized gas are observed along the minor axis of NGC 4418, but we see evidence for ionized gas outflows from VV 655 that may increase the cross-section for gas stripping in grazing collisions. A faint, asymmetric outer arm is detected in NGC 4418 of the type normally associated with galaxy-galaxy interactions.
Conclusions. The simplest model suggests that the minor interaction between VV 655 and NGC 4418 produced the unusual nuclear properties of the LIRG via tidal torquing of the interstellar medium of NGC 4418 rather than through a significant gas transfer event. In addition to inducing a central concentration of gas in NGC 4418, this interaction also produced an enhanced star formation rate and an outer tidal arm in the LIRG. The VV 655-NGC 4418 system offers an example of the potential for minor collisions to alter the evolutionary pathways of giant galaxies
Block Card 4418 Willys Parkway
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: Dwelling (Toledo, Ohio) | Side gabled | Craftsman Style | Homeville Subdivision (Toledo, Ohio) | Willys Park area (Toledo, Ohio) | West Toledo (Toledo, Ohio) | 4418 Willys Parkway (Toledo, Ohio) | Folk House Styl
NGC 4418 ALMA mm-wave spectral scan
No full textVizieR online Data Catalogue associated with article published in journal Astronomy & Astrophysics with title 'Exploring the molecular chemistry and excitation in obscured luminous infrared galaxies: An ALMA mm-wave spectral scan of NGC 4418.' (bibcode: 2015A&A...582A..91C
Soldier, 4418 Quartermaster Service Company, Tokyo, circa 1946
No full textA soldier of the 4418th Quartermaster Service Company serving with the occupation forces in Japan, circa 1946. On the image are noted the number 4418 and the words My Brother Louis(?) G.https://digitalcommons.memphis.edu/speccoll-mss-gattusofj2/1046/thumbnail.jp
RX J0648.0–4418: THE FASTEST-SPINNING WHITE DWARF
Get PDFHD 49798/RX J0648.0-4418 is a post common-envelope X-ray binary composed of a hot subdwarf and one of the most massive white dwarfs with a dynamical mass measurement (1.28±0.05 M☉). This white dwarf, with a spin period of 13.2 s, rotates more than twice faster than the white dwarf in the cataclysmic variable AE Aqr. The current properties of these two binaries, as well as their future evolution, are quite different, despite both contain a fast-spinning white dwarf. HD 49798/RX J0648.0-4418 could be the progenitor of either a Type Ia supernova or of a non-recycled millisecond pulsars. <P /
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