6,063 research outputs found

    Absolute Properties of the Eclipsing Binary Star V501 Herculis

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    V501 Her is a well detached G3 eclipsing binary star with a period of 8.597687 days for which we have determined very accurate light and radial-velocity curves by using robotic telescopes. Results of these data indicate that the component stars have masses of 1.269 +/- 0.004 and 1.211 +/- 0.003 solar masses, radii of 2.001 +/- 0.003 and 1.511 +/- 0.003 solar radii, and temperatures of 5683 +/- 100K and 5720 +/- 100K, respectively. Comparison with the Yonsei-Yale series of evolutionary models results in good agreement at an age of about 5.1 Gyr for a somewhat metal rich composition. Those models indicate that the more massive, larger, slightly cooler star is just beyond core hydrogen exhaustion while the less massive, smaller, slightly hotter star has not quite reached core hydrogen exhaustion. The orbit is not yet circularized, and the components are rotating at or near their pseudosynchronous velocities. The distance to the system is 420 +/- 30 pc

    Fast readout of a single Cooper-pair box using its quantum capacitance

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    We have fabricated a single Cooper-pair box (SCB) together with an on-chip lumped element resonator. By utilizing the quantum capacitance of the SCB, its state can be read out by detecting the phase of a radio-frequency (rf) signal reflected off the resonator. The resonator was optimized for fast readout. By studying quasiparticle tunneling events in the SCB, we have characterized the performance of the readout and found that we can perform a single shot parity measurement in approximately 50 ns. This is an order of magnitude faster than previously reported measurements.Comment: 7 pages, 5 figure

    Negligence—Guest Statute—Owner as a Guest—Wife as a Guest

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    In Naphtali v. Lafazan, defendant and his wife accepted the invitation of plaintiffs, husband and wife, to accompany them on a pleasure trip in an auto owned by plaintiff-husband. It was understood that the expenses of operating the auto were to be borne by plaintiff-husband. As the party proceeded along an Ohio highway, with the defendant driving, the auto left the highway and overturned, injuring the plaintiffs. Suit was instituted in New York, alleging defendant’s ordinary negligence and praying damages for the injuries sustained. Defendant relied upon the Ohio Guest Statute, arguing that plaintiffs were “guests” in the auto and therefore could not recover in the absence of proof of defendant\u27s gross negligence. Two interesting questions were thus presented: (1) Was the plaintiff-owner a “guest” in his own auto, and (2) was the owner’s wife a “guest”? Though there were no Ohio cases in point, the New York Supreme Court held, inter alia, that the owner might recover on proof of defendant’s ordinary negligence, as it was not the intention of the Ohio Legislature to make an owner a “guest” in his own auto. On complicated reasoning, however, plaintiff-wife was found to be a guest and was denied recovery, since there was no proof of defendant’s gross negligence

    Negligence—Guest Statute—Owner as a Guest—Wife as a Guest

    Get PDF
    In Naphtali v. Lafazan, defendant and his wife accepted the invitation of plaintiffs, husband and wife, to accompany them on a pleasure trip in an auto owned by plaintiff-husband. It was understood that the expenses of operating the auto were to be borne by plaintiff-husband. As the party proceeded along an Ohio highway, with the defendant driving, the auto left the highway and overturned, injuring the plaintiffs. Suit was instituted in New York, alleging defendant’s ordinary negligence and praying damages for the injuries sustained. Defendant relied upon the Ohio Guest Statute, arguing that plaintiffs were “guests” in the auto and therefore could not recover in the absence of proof of defendant\u27s gross negligence. Two interesting questions were thus presented: (1) Was the plaintiff-owner a “guest” in his own auto, and (2) was the owner’s wife a “guest”? Though there were no Ohio cases in point, the New York Supreme Court held, inter alia, that the owner might recover on proof of defendant’s ordinary negligence, as it was not the intention of the Ohio Legislature to make an owner a “guest” in his own auto. On complicated reasoning, however, plaintiff-wife was found to be a guest and was denied recovery, since there was no proof of defendant’s gross negligence

    Absolute dimensions of the early F-type eclipsing binary V506 Ophiuchi

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    We report extensive differential V-band photometry and high-resolution spectroscopic observations of the early F-type, 1.06-day detached eclipsing binary V506 Oph. The observations along with times of minimum light from the literature are used to derive a very precise ephemeris and the physical properties for the components, with the absolute masses and radii being determined to 0.7% or better. The masses are 1.4153 +/- 0.0100 M(Sun) and 1.4023 +/- 0.0094 M(sun) for the primary and secondary, the radii are 1.725 +/- 0.010 R(Sun) and 1.692 +/- 0.012 R(Sun), and the effective temperatures 6840 +/- 150 K and 6780 +/- 110 K, respectively. The orbit is circular and the stars are rotating synchronously. The accuracy of the radii and temperatures is supported by the resulting distance estimate of 564 +/- 30 pc, in excellent agreement with the value implied by the trigonometric parallax listed in the Gaia/DR2 catalog. Current stellar evolution models from the MIST series for a composition of [Fe/H] = -0.04 match the properties of both stars in V506 Oph very well at an age of 1.83 Gyr, and indicate they are halfway through their core hydrogen-burning phase.Comment: Accepted for publication in The Astrophysical Journal, 8 pages in emulateapj format including figures and tables. Tables 3, 5, and 6 available only electronically from the Journa

    Absolute dimensions of the unevolved F-type eclipsing binary BT Vulpeculae

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    We report extensive differential V-band photometry and high-resolution spectroscopy for the 1.14 day, detached, double-lined eclipsing binary BT Vul (F0+F7). Our radial-velocity monitoring and light curve analysis lead to absolute masses and radii of M1 = 1.5439 +/- 0.0098 MSun and R1 = 1.536 +/- 0.018 RSun for the primary, and M2 = 1.2196 +/- 0.0080 MSun and R2 = 1.151 +/- 0.029 RSun for the secondary. The effective temperatures are 7270 +/- 150 K and 6260 +/- 180 K, respectively. Both stars are rapid rotators, and the orbit is circular. A comparison with stellar evolution models from the MIST series shows excellent agreement with these determinations, for a composition of [Fe/H] = +0.08 and an age of 350 Myr. The two components of BT Vul are very near the zero-age main sequence.Comment: 9 pages in emulateapj format, including tables and figures. Accepted for publication in The Astrophysical Journa

    Photon generation in an electromagnetic cavity with a time-dependent boundary

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    We report the observation of photon generation in a microwave cavity with a time-dependent boundary condition. Our system is a microfabricated quarter-wave coplanar waveguide cavity. The electrical length of the cavity is varied using the tunable inductance of a superconducting quantum interference device. It is measured in the quantum regime, where the temperature is significantly less than the resonance frequency (~ 5 GHz). When the length is modulated at approximately twice the static resonance frequency, spontaneous oscillations of the cavity field are observed. Time-resolved measurements of the dynamical state of the cavity show multiple stable states. The behavior is well described by theory. Connections to the dynamical Casimir effect are discussed.Comment: 5 pages, 3 Figure

    The quadruple-lined, doubly-eclipsing system V482 Persei

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    We report spectroscopic and differential photometric observations of the A-type system V482 Per that reveal it to be a rare hierarchical quadruple system containing two eclipsing binaries. One has the previously known orbital period of 2.4 days and a circular orbit, and the other a period of 6 days, a slightly eccentric orbit (e = 0.11), and shallow eclipses only 2.3% deep. The two binaries revolve around their common center of mass in a highly elongated orbit (e = 0.85) with a period of 16.67 yr. Radial velocities are measured for all components from our quadruple-lined spectra, and are combined with the light curves and with measurements of times of minimum light for the 2.4 day binary to solve for the elements of the inner and outer orbits simultaneously. The line-of-sight inclination angles of the three orbits are similar, suggesting they may be close to coplanar. The available observations appear to indicate that the 6 day binary experiences significant retrograde apsidal motion in the amount of about 60 degrees per century. We derive absolute masses for the four stars good to better than 1.5%, along with radii with formal errors of 1.1% and 3.5% for the 2.4 day binary and about 9% for the 6 day binary. A comparison of these and other physical properties with current stellar evolution models gives excellent agreement for a metallicity of [Fe/H] = -0.15 and an age of 360 Myr.Comment: 15 pages in emulateapj format, including figures and tables. Accepted for publication in The Astrophysical Journa
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