The paper ‘Evidence for an intermediate-mass black hole in the globular cluster NGC 6624’ was published in MNRAS, 468, 2114 (2017). When estimating the model-dependent minimum mass of the ...intermediate-mass black hole (IMBH) of 60 000 M⊙ in Section 5, we used the separation of 0.15 pc for PSR J1823−3021C from the globular cluster centre, as given in Peuten et al. (2014, see table 2 therein). Unfortunately, this value is incorrect and the correct separation is 0.34 pc based on the position given in Table 1 (also see Lynch et al. 2012). This correct distance measurement changes the result presented in Fig. 9 in the published version, and the modified figure based on the positions given in Table 1 is appended here. Note that this does not affect any other results presented in the paper, in particular, the IMBH mass estimation obtained through orbital dynamics given in Section 4.
HYPERLEDA Paturel, G.; Theureau, G.; Bottinelli, L. ...
Astronomy and astrophysics (Berlin),
12/2003, Volume:
412, Issue:
1
Journal Article
Peer reviewed
Open access
After a compilation of HI data from 611 references and new observations made in Nancay, we produce a catalog of homogenized HI data for 16781 galaxies. The homogenization is made using the EPIDEMIC ...method from which all data are progressively converted into the adopted standard. The result is a catalog giving: 1) the logarithm of twice the maximum rotation velocity, log 2V(M)(sini) M, converted to the system of Mathewson et al. (1996). This quantity is given without correction for inclination; 2) the HI magnitude, m(21), ( area of the 21-cm line width expressed in magnitude) converted to the flux system of Theureau et al. (1998); 3) the HI velocity, V-HI, expressed with the optical definition (i.e., using wavelengths instead frequencies). The typical uncertainties are: 0.04 for log 2V(M)(sin i) 0.25 mag for m(21) and 9 km s(-1) for V-HI.
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PSR J1802 - 2124 is a 12.6 ms pulsar in a 16.8 hr binary orbit with a relatively massive white dwarf (WD) companion. These properties make it a member of the intermediate-mass class of binary pulsar ...(IMBP) systems. We have been timing this pulsar since its discovery in 2002. Concentrated observations at the Green Bank Telescope, augmented with data from the Parkes and Nançay observatories, have allowed us to determine the general relativistic Shapiro delay. This has yielded pulsar and WD mass measurements of 1.24 ± 0.11 M sun and 0.78 ± 0.04 M sun (68% confidence), respectively. The low mass of the pulsar, the high mass of the WD companion, the short orbital period, and the pulsar spin period may be explained by the system having gone through a common-envelope phase in its evolution. We argue that selection effects may contribute to the relatively small number of known IMBPs.
The paper ‘Placing limits on the stochastic gravitational-wave background using European Pulsar Timing Array data’ was published in Mon. Not. R. Astron. Soc. 414, 3117–3128 (2011).
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We announce the discovery of 1-100 GeV gamma-ray emission from the archetypal TeV pulsar wind nebula (PWN) HESS J1825--137 using 20 months of survey data from the Fermi-Large Area Telescope (LAT). ...The gamma-ray emission detected by the LAT is significantly spatially extended, with a best-fit rms extension of Delta *s = 056 ? 007 for an assumed Gaussian model. The 1-100 GeV LAT spectrum of this source is well described by a power law with a spectral index of 1.38 ? 0.12 ? 0.16 and an integral flux above 1 GeV of (6.50 ? 0.21 ? 3.90) X 10--9 cm--2 s--1. The first errors represent the statistical errors on the fit parameters, while the second ones are the systematic uncertainties. Detailed morphological and spectral analyses bring new constraints on the energetics and magnetic field of the PWN system. The spatial extent and hard spectrum of the GeV emission are consistent with the picture of an inverse Compton origin of the GeV-TeV emission in a cooling-limited nebula powered by the pulsar PSR J1826--1334.
We report the discovery of the millisecond pulsar PSR J2043+1711 in a search of a Fermi Large Area Telescope (LAT) source with no known associations, with the Nancay Radio Telescope. The new pulsar, ...confirmed with the Green Bank Telescope, has a spin period of 2.38 ms, is relatively nearby (d approx. < 2 kpc) and is in a 1.48-d orbit around a low-mass companion, probably an He-type white dwarf. Using an ephemeris based on Arecibo, Nancay and Westerbork timing measurements, pulsed gamma-ray emission was detected in the data recorded by the Fermi LAT. The gamma-ray light curve and spectral properties are typical of other gamma-ray millisecond pulsars seen with Fermi. X-ray observations of the pulsar with Suzaku and the Swift X-ray Telescope yielded no detection. At 1.4 GHz, we observe strong flux density variations because of interstellar diffractive scintillation; however, a sharp peak can be observed at this frequency during bright scintillation states. At 327 MHz, the pulsar is detected with a much higher signal-to-noise ratio and its flux density is far more steady. However, at that frequency the Arecibo instrumentation cannot yet fully resolve the pulse profile. Despite that, our pulse time-of-arrival measurements have a post-fit residual rms of 2 micro s. This and the expected stability of this system have made PSR J2043+1711 one of the first new Fermi-selected millisecond pulsars to be added to pulsar gravitational wave timing arrays. It has also allowed a significant measurement of relativistic delays in the times of arrival of the pulses due to the curvature of space-time near the companion, but not yet with enough precision to derive useful masses for the pulsar and the companion. Nevertheless, a mass for the pulsar between 1.7 and 2.0 solar Mass can be derived if a standard millisecond pulsar formation model is assumed. In this paper, we also present a comprehensive summary of pulsar searches in Fermi LAT sources with the Nancay Radio Telescope to date.
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Pulsars PSR J0248+6021 (rotation period P=217 ms and spin-down power Edot = 2.13E35 erg/s) and PSR J2240+5832 (P=140 ms, Edot = 2.12E35 erg/s) were discovered in 1997 with the Nancay radio telescope ...during a northern Galactic plane survey, using the Navy-Berkeley Pulsar Processor (NBPP) filter bank. GeV gamma-ray pulsations from both were discovered using the Fermi Large Area Telescope. Twelve years of radio and polarization data allow detailed investigations. The two pulsars resemble each other both in radio and in gamma-ray data. Both are rare in having a single gamma-ray pulse offset far from the radio peak. The high dispersion measure for PSR J0248+6021 (DM = 370 pc cm^-3) is most likely due to its being within the dense, giant HII region W5 in the Perseus arm at a distance of 2 kpc, not beyond the edge of the Galaxy as obtained from models of average electron distributions. Its high transverse velocity and the low magnetic field along the line-of-sight favor this small distance. Neither gamma-ray, X-ray, nor optical data yield evidence for a pulsar wind nebula surrounding PSR J0248+6021. The gamma-ray luminosity for PSR J0248+6021 is L_ gamma = (1.4 \pm 0.3)\times 10^34 erg/s. For PSR J2240+5832, we find either L_gamma = (7.9 \pm 5.2) \times 10^34 erg/s if the pulsar is in the Outer arm, or L_gamma = (2.2 \pm 1.7) \times 10^34 erg/s for the Perseus arm. These luminosities are consistent with an L_gamma ~ sqrt(Edot) rule. Comparison of the gamma-ray pulse profiles with model predictions, including the constraints obtained from radio polarization data, favor emission in the far magnetosphere. These two pulsars differ mainly in their inclination angles and acceleration gap widths, which in turn explains the observed differences in the gamma-ray peak widths.
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We have timed four millisecond pulses, PSRs J1721-2457, J1745–0952, J1810–2005, and J1918–0642, for up to a total of 10.5 years each using multiple telescopes in the European Pulsar Timing Array ...network: the Westerbork Synthesis Radio Telescope in The Netherlands, the Nançay Radio Telescope in France and the Lovell telescope at Jodrell Bank in the UK. The long time span has enabled us to measure the proper motions of J1745–0952 and J1918–0642, indicating that they have transverse velocities of 200(50) and 54(7) km s-1 respectively. We have obtained upper limits on the proper motion of J1721–2457 and J1810–2005, which imply that they have transverse velocities less than 140 and 400 km s-1 respectively. In all cases, the velocities lie in the range typical of millisecond pulsars. We present pulse profiles for each pulsar taken from observations at multiple frequencies in the range of 350 to 2600 MHz, and show that J1810–2005 shows significant profile evolution in this range. Using our multi-frequency observations, we measured the spectral indices for all four pulsars, and for J1810–2005 it appears to be very flat. The flux density of J1918–0642 shows extensive modulation which we attribute to the combined effects of refractive and diffractive scintillation. We discuss the possible use of including J1721–2457 or J1918–0642 in a pulsar timing array, and find that J1918–0642 will be useful to include when the timing precision of this pulsar is improved over the next few years. We have searched archival optical observations to detect companions of the binary pulsars, but none were detected. However, we provide lower limits on the masses of the white dwarf companions of PSRs J1745–0952 and J1918–0642.
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Context. Millisecond pulsars (MSPs) represent nearly half of the more than 160 currently known γ-ray pulsars detected by the Large Area Telescope on the Fermi satellite, and a third of all known MSPs ...are seen in γ rays. The least energetic γ-ray MSPs enable us to probe the so-called deathline for high-energy emission, i.e., the spin-down luminosity limit under which pulsars (PSRs) cease to produce detectable high-energy radiation. Characterizing the MSP luminosity distribution helps to determine their contribution to the Galactic diffuse γ-ray emission. Aims. Because of the Shklovskii effect, precise proper motion and distance measurements are key ingredients for determining the spin-down luminosities of MSPs accurately. Our aim is to obtain new measurements of these parameters for γ-ray MSPs when possible, and clarify the relationship between the γ-ray luminosity of pulsars and their spin-down luminosity. Detecting low spin-down luminosity pulsars in γ rays and characterizing their spin properties is also particularly interesting for constraining the deathline for high-energy emission. Methods. We made use of the high-quality pulsar timing data recorded at the Nançay Radio Telescope over several years to characterize the properties of a selection of MSPs. For one of the pulsars, the dataset was complemented with Westerbork Synthesis Radio Telescope observations. The rotation ephemerides derived from this analysis were also used to search the LAT data for new γ-ray MSPs. Results. For the MSPs considered in this study, we obtained new transverse proper motion measurements or updated the existing ones, and placed new distance constraints for some of them, with four new timing parallax measurements. We discovered significant GeV γ-ray signals from four MSPs, i.e., PSRs J0740+6620, J0931−1902, J1455−3330, and J1730−2304. The latter is now the least energetic γ-ray pulsar found to date. Despite the improved Ė and Lγ estimates, the relationship between these two quantities remains unclear, especially at low Ė values.
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