Publications (81)
Searches for diffuse X-ray emission around millisecond pulsars: An X-ray nebula associated with PSR J2124-3358
C. Y. Hui, W. Becker
We report on diffuse X-ray emission associated with the nearby solitary millisecond pulsar PSR J2124-3358 detected with XMM-Newton and Chandra. The emission extends from the pulsar…
XMM-Newton Observations of PSR B1957+20
H. H. Huang, W. Becker
We report on XMM-Newton observations of the Black Widow pulsar, PSR B1957+20. The pulsar's X-ray emission is non-thermal and best modeled with a single powerlaw spectrum of photon…
Geminga: a tale of two tails, and much more
P. A. Caraveo, G. F. Bignami, A. De Luca +5
We report on the deep (100 ksec) XMM-Newton/EPIC observation of the field of the Geminga pulsar. The unprecedented throughput of the instrument allowed to detect two elongated para…
Electron-electron dynamics in laser-induced nonsequential double ionization
C. Figueira de Morisson Faria, X. Liu, H. Schomerus +1
For the description of nonsequential double ionization (NSDI) of rare-gas atoms by a strong linearly polarized laser field, the quantum-mechanical -matrix diagram that incorpora…
A search for X-ray counterparts of the millisecond pulsars in the globular cluster M28 (NGC 6626)
W. Becker, C. Y. Hui
A recent radio survey of globular clusters has increased the number of millisecond pulsars drastically. M28 is now the globular cluster with the third largest population of known p…
X-ray observations of RX J0822-4300 and Puppis-A
C. Y. Hui, W. Becker
Based on observations with the X-ray observatories Chandra and XMM-Newton we present results from a detailed spectro-imaging and timing analysis of the central compact X-ray source…
TRAPUM search for pulsars in supernova remnants and pulsar wind nebulae -- I. Survey description and initial discoveries
J. D. Turner, B. W. Stappers, E. Carli +18
We present the description and initial results of the TRAPUM (TRAnsients And PUlsars with MeerKAT) search for pulsars associated with supernova remnants (SNRs), pulsar wind nebulae…
X-ray emission properties of the old pulsar PSR B2224+65
C. Y. Hui, W. Becker
Using archival Chandra data we studied the X-ray emission properties of PSR B2224+65 and its environment. Albeit limited by photon statistics the spectral analysis suggests that th…
The X-ray nebula of the filled center supernova remnant 3C58 and its interaction with the environment
F. Bocchino, R. S. Warwick, P. Marty +3
An \xmm observation of the plerionic supernova remnant 3C58 has allowed us to study the X-ray nebula with unprecedented detail. A spatially resolved spectral analysis with a resolu…
Search for the Optical Counterpart of the Vela Pulsar X-ray Nebula
R. P. Mignani, A. De Luca, O. Kargaltsev +4
Observations of the Vela pulsar region with the Chandra X-ray observatory have revealed the fine structure of its synchrotron pulsar-wind nebula (PWN), which showed an overall simi…
X-ray Counterparts of Millisecond Pulsars in Globular Clusters
W. Becker, H. H. Huang, T. Prinz
We have systematically studied the X-ray emission properties of globular cluster millisecond pulsars in order to evaluate their spectral properties and luminosities in a uniform wa…
HST proper motion confirms the optical detection of PSR B1929+10
A. De Luca, R. P. Mignani, P. A. Caraveo +1
We have measured the proper motion of the candidate optical counterpart of the old, nearby pulsar PSR B1929+10, using a set of HST/STIS images collected in 2001, 7.2 years after th…
X-rays from the Eclipsing Millisecond Pulsar PSR J1740-5340 in the Globular Cluster NGC 6397
R. H. H. Huang, W. Becker
The millisecond pulsar PSR J1740-5340 in the globular cluster NGC 6397 shows radio eclipses over ~40% of its binary orbit. A first Chandra observation revealed indications for the…
eROSITA Science Book: Mapping the Structure of the Energetic Universe
A. Merloni, P. Predehl, W. Becker +22
eROSITA is the primary instrument on the Russian SRG mission. In the first four years of scientific operation after its launch, foreseen for 2014, it will perform a deep survey of…
Interference effects in above-threshold ionization from diatomic molecules: determining the internuclear separation
H. Hetzheim, C. Figueira de Morisson Faria, W. Becker
We calculate angle-resolved above-threshold ionization spectra for diatomic molecules in linearly polarized laser fields, employing the strong-field approximation. The interference…
High-order above-threshold ionization: the uniform approximation and the effect of the binding potential
C. Figueira de Morisson Faria, H. Schomerus, W. Becker
A versatile semiclassical approximation for intense laser-atom processes is presented. This uniform approximation is no more complicated than the frequently-used multi-dimensional…
BeppoSAX observation of PSR B1937+21
L. Nicastro, G. Cusumano, O. Loehmer +5
We present the results of a BeppoSAX observation of the fastest rotating pulsar known: PSR B1937+21. The ~200 ks observation (78.5 ks MECS/34 ks LECS on-source time) allowed us to…
X-ray Observations of Neutron Stars and Pulsars: First Results from XMM-Newton
W. Becker, B. Aschenbach
The X-ray Multi-Mirror Mission XMM-Newton is ESA's largest observatory so far; it is dedicated to explore the Universe in the 0.2 - 15 keV X-ray band of the electromagnetic spectru…
The supernova remnants G67.7+1.8, G31.5-0.6 and G49.2-0.7
F. Mavromatakis, J. Papamastorakis, J. Ventura +3
Wide field CCD observations of three, less known, supernova remnants. Filamentary and diffuse emission is discovered from the supernova remnant G67.7+1.8. Emission can also be seen…
INTEGRAL observations of PSR B0540-69
A. Slowikowska, G. Kanbach, J. Borkowski +1
PSR B0540-69 is often called an extragalactic 'twin' of the Crab pulsar in the Large Magellanic Cloud. The pulsar is embedded in a synchrotron nebula in the center of SNR 0540-69.3…
Pathway to the Square Kilometre Array - The German White Paper -
F. Aharonian, T. G. Arshakian, B. Allen +69
The Square Kilometre Array (SKA) is the most ambitious radio telescope ever planned. With a collecting area of about a square kilometre, the SKA will be far superior in sensitivity…
ROSAT observations of the radio and gamma-ray pulsar PSR 1706-44
W. Becker, K. T. S. Barzier, J. Truemper
We report on the detection of PSR 1706-44 in two ROSAT-PSPC observations. The recorded source counts are unpulsed with a pulsed fraction upper limit of 18%. Spectral analysis…
Hoinga: A supernova remnant discovered in the SRG/eROSITA All-Sky Survey eRASS1
W. Becker, N. Hurley-Walker, Ch. Weinberger +4
Supernova remnants (SNRs) are observable for about 6-15x10^4 years before they fade into the Galactic interstellar medium. With a Galactic supernova rate of approximately two per c…
Discovery of an X-ray Nebula associated with PSR J2124-3358
C. Y. Hui, W. Becker
We report the discovery of an X-ray nebula associated with the nearby millisecond pulsar PSR J2124-3358. This is the first time that extended emission from a solitary millisecond p…
The warm-hot circumgalactic medium of the Milky Way as seen by eROSITA
N. Locatelli, G. Ponti, X. Zheng +7
The first all-sky maps of the diffuse emission of high ionization lines observed in X-rays by SRG/eROSITA, provide an excellent probe for the study of the warm-hot phase (T~10^6 K)…
ROSAT observations of PSR 2334+61 in the supernova remnant G114.3+0.3
W. Becker, K. T. S. Barzier, J. Trümper
We report on the observation of PSR 2334+61 in the soft X-ray domain with ROSAT. Assuming a power-law spectrum with photon-index we derive an X-ray fl…
Resolving the bow-shock nebula around the old pulsar PSR B1929+10 with multi-epoch Chandra observations
C. Y. Hui, W. Becker
We have studied the nearby old pulsar PSR B1929+10 and its surrounding interstellar medium utilizing the sub-arcsecond angular resolution of the Chandra X-ray Observatory. The Chan…
ASKAP EMU Radio Detection of the Reflection Nebula VdB-80 in the Monoceros Crossbones Filamentary Structure
A. C. Bradley, Z. J. Smeaton, N. F. H. Tothill +9
We present a new radio detection from the Australian Square Kilometre Array Pathfinder (ASKAP) Evolutionary Map of the Universe (EMU) survey associated with the reflection nebula (…
ROSAT HRI Observations of the Crab Pulsar: An Improved Temperature upper limit for PSR 0531+21
W. Becker, B. Aschenbach
ROSAT HRI observations have been used to determine an upper limit of the Crab pulsar surface temperature from the off-pulse count rate. For a neutron star mass of 1.4 \Mo and a rad…
Multiwavelength study of supernova remnants in the Circinus constellation with SRG/eROSITA
A. Khokhriakova, W. Becker
The paper combines optical, radio, and eROSITA X‑ray data to search for and characterize supernova remnant candidates in the Circinus constellation, identifying several new candida…
Chandra X-Ray Observatory Observations of the Globular Cluster M71
R. F. Elsner, C. O. Heinke, H. N. Cohn +12
We observed the nearby, low-density globular cluster M71 (NGC 6838) with the Chandra X-ray Observatory to study its faint X-ray populations. Five X-ray sources were found inside th…
Exploring the Central Compact Object in the RX J0852.0-4622 Supernova Remnant with XMM-Newton
W. Becker, C. Y. Hui, B. Aschenbach +1
The properties of the presumably young galactic supernova remnant (SNR) RX J0852.0-4622, discovered by ROSAT, are still uncertain. The data concerning the distance to the SNR, its…
G321.3-3.9: A new supernova remnant observed with multi-band radio data and in the SRG/eROSITA All-Sky Surveys
S. Mantovanini, W. Becker, A. Khokhriakova +3
G321.3-3.9 was first identified as a partial shell at radio frequencies a few decades ago. Although it continued to be observed, no additional studies were undertaken until recentl…
The Milky Way - Pulsars and Isolated Neutron Stars
W. Becker, G. G. Pavlov
CONTENTS The Milky Way -- Pulsars and Isolated Neutron Stars / Introduction: Historical Overview / Physics and Astrophysics of Isolated Neutron Stars / Rotation-powered Pulsars: Th…
Radio and X-ray nebulae associated with PSR J1509-5850
C. Y. Hui, W. Becker
We have discovered a long radio trail at 843 MHz which is apparently associated with middle age pulsar PSR J1509-5850. The radio trail has a length of ~7 arcmin. In X-rays, Chandra…
The X-ray emission properties of millisecond pulsars
W. Becker, J. Trümper
Until now X-radiation from nine millisecond pulsars has been detected. In the present paper we summarize the observations and show the results of a re-analysis of archival ROSAT da…
BeppoSAX observations of the three Gamma-ray pulsars PSR B0656+14, PSR B1055-52 and PSR B1706-44
T. Mineo, E. Massaro, G. Cusumano +1
We report the results of the observations of the three gamma-ray pulsars PSR B0656+14, PSR B1055-52 and PSR B1706-44 performed with BeppoSAX. We detected a pulsed emission only for…
Low-mass stars dominate the hot (0.7 keV) Galactic X-ray emission
G. Ponti, M. C. H. Yeung, G. Stel +12
The circumgalactic medium (CGM) of the Milky Way is composed of a tenuous atmosphere filled with multi-phase plasma, including a warm-hot virialised component. Recent studies sugge…
The TRAPUM Small Magellanic Cloud pulsar survey with MeerKAT: I. Discovery of seven new pulsars and two Pulsar Wind Nebula associations
E. Carli, L. Levin, B. W. Stappers +17
The sensitivity of the MeerKAT radio interferometer is an opportunity to probe deeper into the population of rare and faint extragalactic pulsars. The TRAPUM (TRAnsients and PUlsar…
Pulse phase variations of the X-ray spectral features in the radio-quiet neutron star 1E 1207-5209
S. Mereghetti, A. De Luca, P. A. Caraveo +3
We present the results of an XMM-Newton observation of the radio-quiet X-ray pulsar 1E 1207-5209 located at the center of the shell-like supernova remnant G296.5+10.0. The X-ray sp…
The nature of the infrared counterpart and of the optical nebula associated with the Central Compact Object in Vela Jr.\
R. P. Mignani, A. De Luca, S. Zharikov +3
The X-ray source CXO\, J085201.4461753in the few kyr-old Vela Jr. supernova remnant (G266.2-1.2) belongs to the peculiar class of isolated neutron stars dubbed "Central Compact…
Study of HST counterparts to Chandra X-ray sources in the Globular Cluster M71
R. H. H. Huang, W. Becker, P. D. Edmonds +3
We report on archival Hubble Space Telescope (HST) observations of the globular cluster M71 (NGC 6838). These observations, covering the core of the globular cluster, were performe…
The SRG/eROSITA All-Sky Survey DR2: Cumulative X-ray catalogues from the first three surveys and multi-wavelength counterparts in the western Galactic hemisphere
M. E. Ramos-Ceja, G. Lamer, M. Salvato +111
The paper presents the second data release of the SRG/eROSITA all‑sky survey, providing catalogues of nearly two million X‑ray sources (point‑like and extended) from the first thre…
Precise Localization of the Soft Gamma Repeater SGR 1627-41 and the Anomalous X-ray Pulsar AXP 1E1841-045 with Chandra
S. Wachter, S. Patel, C. Kouveliotou +7
We present precise localizations of AXP 1E1841-045 and SGR 1627-41 with Chandra. We obtained new infrared observations of SGR 1627-41 and reanalyzed archival observations of AXP 1E…
X-ray Radiation from the Millisecond Pulsar J0437-4715
V. E. Zavlin, G. G. Pavlov, D. Sanwal +4
We report on spectral and timing observations of the nearest millisecond pulsar J0437-4715 with Chandra. The pulsar spectrum, detected up to 7 keV, cannot be described by a simple…
Simultaneous monitoring of the two coupled motors of a single FoF1-ATP synthase by three-color FRET using duty cycle-optimized triple-ALEX
N. Zarrabi, S. Ernst, M. G. Dueser +5
FoF1-ATP synthase is the enzyme that provides the 'chemical energy currency' adenosine triphosphate, ATP, for living cells. The formation of ATP is accomplished by a stepwise inter…
Resonant enhancements of high-order harmonic generation
C. Figueira de Morisson Faria, R. Kopold, W. Becker +1
Solving the one-dimensional time-dependent Schrödinger equation for simple model potentials, we investigate resonance-enhanced high-order harmonic generation, with emphasis on the…
Pulsars with the Australian Square Kilometre Array Pathfinder
I. H. Stairs, M. J. Keith, Z. Arzoumanian +33
The Australian Square Kilometre Array Pathfinder (ASKAP) is a 36-element array with a 30-square-degree field of view being built at the proposed SKA site in Western Australia. We a…
Multi-wavelength observations of 3FGL J2039.6-5618: a candidate redback millisecond pulsar
D. Salvetti, R. P. Mignani, A. De Luca +8
We present multi-wavelength observations of the unassociated gamma-ray source 3FGL J2039.6-5618 detected by the Fermi Large Area Telescope. The source gamma-ray properties suggest…
Coulomb repulsion and quantum-classical correspondence in laser-induced nonsequential double ionization
C. Figueira de Morisson Faria, X. Liu, H. Schomerus +1
The influence of electron-electron Coulomb repulsion on nonsequential double ionization of rare-gas atoms is investigated. Several variants of the quantum-mechanical transition amp…
The putative pulsar-wind nebulae of the three Musketeers PSR B1055-52, B0656+14 and Geminga revisited
W. Becker, N. Kawai, W. Brinkmann +1
We report on the analysis of archival ASCA, ROSAT and BeppoSAX data of PSR B1055-52, PSR B0656+14 and Geminga, performed in order to investigate the reality of the putative ~10-20…
Detection of large-scale X-ray bubbles in the Milky Way halo
P. Predehl, R. A. Sunyaev, W. Becker +25
The halo of the Milky Way provides a laboratory to study the properties of the shocked hot gas that is predicted by models of galaxy formation. There is observational evidence of e…
Delay-dependent amplification of a probe pulse via stimulated Rayleigh scattering
M. V. Fedorov, S. V. Popruzhenko, D. F. Zaretsky +1
Stimulated Rayleigh scattering of pump and probe light pulses of close carrier frequencies is considered. A nonzero time delay between the two pulses is shown to give rise to ampli…
The TRAPUM L-band survey for pulsars in Fermi-LAT gamma-ray sources
C. J. Clark, R. P. Breton, E. D. Barr +35
More than 100 millisecond pulsars (MSPs) have been discovered in radio observations of gamma-ray sources detected by the Fermi Large Area Telescope (LAT), but hundreds of pulsar-li…
The SRG/eROSITA all-sky survey: First X-ray catalogues and data release of the western Galactic hemisphere
A. Merloni, G. Lamer, T. Liu +142
The eROSITA telescope array aboard the Spektrum Roentgen Gamma (SRG) satellite began surveying the sky in December 2019, with the aim of producing all-sky X-ray source lists and sk…
The eROSITA X-ray telescope on SRG
P. Predehl, R. Andritschke, V. Arefiev +90
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the primary instrument on the Spectrum-Roentgen-Gamma (SRG) mission, which was successfully launched on July 1…
A Catalog of Galactic Supernova Remnants and Supernova Remnant Candidates from the EMU/POSSUM Radio Sky Surveys. I
B. D. Ball, R. Kothes, E. Rosolowsky +16
We use data from the EMU (Evolutionary Map of the Universe) and POSSUM (Polarization Sky Survey of the Universe's Magnetism) radio southern sky surveys, conducted with the Australi…
XMM-Newton observations of the supernova remnant RX J0852.0-4622/GRO J0852-4642
A. F. Iyudin, B. Aschenbach, W. Becker +2
RX J0852.0-4622 is a shell type supernova remnant with a power law spectrum in the south-eastern corner of the Vela supernova remnant. We report XMM-Newton observations of three fi…
Landau damping in thin films irradiated by a strong laser field
D. F. Zaretsky, Ph. A. Korneev, S. V. Popruzhenko +1
The rate of linear collisionless damping (Landau damping) in a classical electron gas confined to a heated ionized thin film is calculated. The general expression for the imaginary…
On the Present and Future of Pulsar Astronomy
W. Becker, J. Gil, B. Rudak
To face recent observational results obtained in multi-wavelength studies from neutron stars and pulsars with the various theoretical models and to discuss on future perspectives o…
Extracting photoelectron spectra from the time-dependent wave function: Comparison of the projection onto continuum states and window-operator methods
B. FetiÄ, W. Becker, D. B. MiloÅ¡eviÄ
Over the last three decades numerous numerical methods for solving the time-dependent Schrödinger equation within the single-active electron approximation have been developed for…
A multi-wavelength investigation of candidate milli-second pulsars in unassociated -ray sources
D. Salvetti, R. P. Mignani, A. De Luca +7
About one third of the 3033 -ray sources in the Third Fermi-LAT Gamma-ray Source Catalogue (3FGL) are unidentified and do not have even a tentative association with a known obj…
Exploring the X-ray emission properties of the supernova remnant G67.7+1.8 and its central X-ray sources
C. Y. Hui, W. Becker
We have studied the supernova remnant G67.7+1.8 with the Chandra X-ray observatory. The remnant's X-ray morphology correlates well with the double-arc structure seen at radio wavel…
Probing the Proper Motion of the Central Compact Object in Puppis-A with the Chandra High Resolution Camera
C. Y. Hui, W. Becker
By making use of the sub-arcsecond angular resolution of the High Resolution Camera (HRC-I) aboard the Chandra X-ray satellite we have examined the central compact object RX J0822-…
The 2-10 keV emission properties of PSR B1937+21
L. Nicastro, G. Cusumano, L. Kuiper +3
We present the results of a BeppoSAX observation of the fastest pulsar known: PSR B1937+21. The ~ 200 ks observation (78.5 (34) ks MECS (LECS) exposure times) allowed us to investi…
The TRAPUM Small Magellanic Cloud pulsar survey with MeerKAT -- II. Nine new radio timing solutions and glitches from young pulsars
E. Carli, D. Antonopoulou, M. Burgay +17
We report new radio timing solutions from a three-year observing campaign conducted with the MeerKAT and Murriyang telescopes for nine Small Magellanic Cloud pulsars, increasing th…
Can we measure the Wigner time delay in a photoionization experiment?
B. FetiÄ, W. Becker, D. B. MiloÅ¡eviÄ
No, we cannot! The concept of Wigner time delay was introduced in scattering theory to quantify the delay or advance of an incoming particle in its interaction with the scattering…
Attosecond double-slit experiment
F. Lindner, M. G. Schaetzel, H. Walther +7
A new scheme for a double-slit experiment in the time domain is presented. Phase-stabilized few-cycle laser pulses open one to two windows (``slits'') of attosecond duration for ph…
Capture into Rydberg states and momentum distributions of ionized electrons
N. I. Shvetsov-Shilovski, S. P. Goreslavski, S. V. Popruzhenko +1
The yield of neutral excited atoms and low-energy photoelectrons generated by the electron dynamics in the combined Coulomb and laser field after tunneling is investigated. We pres…
The Salamander: A case study of the magnetic field and peculiar morphology of G309.8-2.6 through radio polarimetry
Wenhui Jing, Jennifer L. West, Xiaohui Sun +17
Studying the interaction between core-collapse supernova remnants (SNRs) and their surrounding environments is essential to understanding the mechanism for energy transfer to the i…
The X-ray luminosity of rotation-powered neutron stars
W. Becker, J. Trümper
As a result of recent observations with ROSAT and ASCA the number of rotation-powered pulsars seen at X-ray energies has increased substantially. In this paper we review the phenom…
The XMM-Newton view of the radio-quiet neutron star 1E 1207.4-5209
A. De Luca, S. Mereghetti, P. A. Caraveo +3
We have observed the radio-quiet X-ray pulsar 1E 1207.4-5209 with the high throughput EPIC cameras onboard XMM-Newton. The spectrum of this peculiar source is characterized by two…
The Curious Case of the "Heartworm" Nebula
W. D. Cotton, F. Camilo, W. Becker +9
The curious Galactic features near G357.20.2 were observed with the MeerKAT radio interferometer array in the UHF and L bands (0.56--1.68 GHz). There are two possibly related fe…
EMU: Evolutionary Map of the Universe
Ray P. Norris, A. M. Hopkins, J. Afonso +54
EMU is a wide-field radio continuum survey planned for the new Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The primary goal of EMU is to make a deep (rms ~ 10 m…
Searching for X-Ray Counterparts of Degree Wide TeV Halos Around Middle-Aged Pulsars with SRG/eROSITA
A. Khokhriakova, W. Becker, G. Ponti +3
Context. Extended gamma-ray TeV emission (TeV halos) around middle-aged pulsars has been detected. A proposed model to explain these TeV halos is that electrons from a degree-wide…
Spectral and timing properties of the X-ray emission from the millisecond pulsar PSR B1821-24
T. Mineo, G. Cusumano, E. Massaro +2
We report results on the timing and spectral analysis of observations of the millisecond pulsar PSR B1821-24 with RXTE, BeppoSAX and Chandra. The X-ray light curve is characterized…
Strong-field approximation for intense-laser atom processes: the choice of gauge
D. Bauer, D. B. Milosevic, W. Becker
The strong-field approximation can be and has been applied in both length gauge and velocity gauge with quantitatively conflicting answers. For ionization of negative ions with a g…
Chandra X-Ray Observatory observations of the globular cluster M28 and its millisecond pulsar B1821-24
W. Becker, D. A. Swartz, G. G. Pavlov +8
We report here the results of the first Chandra X-Ray Observatory observations of the globular cluster M28 (NGC 6626). 46 X-ray sources are detected, of which 12 lie within one cor…
A Fast-Moving Central Compact Object in Puppis-A
C. Y. Hui, W. Becker
Utilizing two Chandra High Resolution Camera (HRC-I) observations with an epoch separation of somewhat more than five years, we have measured the proper motion of the central compa…
Pulse shape and spectrum of PSR J0218+4232 observed with BeppoSAX
T. Mineo, G. Cusumano, L. Kuiper +9
We present the results of a BeppoSAX observation of PSR J0218+4232 which, for the first time, provides detailed information on the pulsar's temporal and spectral emission propertie…
Nonsequential double ionization: a comparison of classical simulations and -matrix results
Phay J. Ho, X. Liu, W. Becker
In a fully classical simulation, we investigate the recollision mechanism of non-sequential double ionization (NSDI) and its manifestation in the end-of-pulse electron momentum dis…