Benjamin Knispel
A5010808685- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Astrophysical Phenomena and Observations
- Planetary Science and Exploration
- Radio Astronomy Observations and Technology
- Spaceflight effects on biology
- History and Developments in Astronomy
- Computational Physics and Python Applications
- Astronomy and Astrophysical Research
- Space Science and Extraterrestrial Life
- Astronomical Observations and Instrumentation
- Stellar, planetary, and galactic studies
- High-pressure geophysics and materials
- Space Exploration and Technology
- Space exploration and regulation
- Ionosphere and magnetosphere dynamics
- Physics and Engineering Research Articles
- Spacecraft and Cryogenic Technologies
- Linguistics and language evolution
- Geophysics and Sensor Technology
- German Literature and Culture Studies
- Space Satellite Systems and Control
Max Planck Institute for Gravitational Physics
2012-2022
Leibniz University Hannover
2012-2019
University of Wisconsin–Milwaukee
2017
Max Planck Society
2008-2014
Recent work has exploited pulsar survey data to identify temporally isolated, millisecond-duration radio bursts with large dispersion measures (DMs). These have been interpreted as arising from a population of extragalactic sources, in which case they would provide unprecedented opportunities for probing the intergalactic medium; may also be linked new source classes. Until now, however, all so-called fast (FRBs) detected Parkes telescope and its 13-beam receiver, casting some concern about...
We report the discovery and initial follow-up of a double neutron star (DNS) system, PSR J1946$+$2052, with Arecibo L-Band Feed Array pulsar (PALFA) survey. J1946$+$2052 is 17-ms in 1.88-hour, eccentric ($e \, =\, 0.06$) orbit $\gtrsim 1.2 M_\odot$ companion. have used Jansky Very Large to localize precision 0.09 arcseconds using new phase binning mode. searched multiwavelength catalogs for coincident sources but did not find any counterparts. The improved position enabled measurement spin...
In the modern era of big data, many fields astronomy are generating huge volumes analysis which can sometimes be limiting factor in research. Fortunately, computer scientists have developed powerful data-mining techniques that applied to various fields. this paper, we present a novel artificial intelligence (AI) program identifies pulsars from recent surveys by using image pattern recognition with deep neural nets—the PICS (Pulsar Image-based Classification System) AI. The AI mimics human...
We report here the Einstein@Home discovery of PSR J1913+1102, a 27.3-ms pulsar found in data from ongoing Arecibo PALFA survey. The is 4.95-hr double neutron star (DNS) system with an eccentricity 0.089. From radio timing 305-m telescope, we measure rate advance periastron to be 5.632(18) deg/yr. Assuming general relativity accurately models orbital motion, this corresponds total mass 2.875(14) solar masses, similar most massive DNS known date, B1913+16, but much smaller eccentricity. small...
The on-going PALFA survey at the Arecibo Observatory began in 2004 and is searching for radio pulsars Galactic plane 1.4 GHz. Observations since 2009 have been made with new wider-bandwidth spectrometers than were previously employed this survey. A data reduction pipeline has place mid-2011 which consists of standard methods using dedispersion, searches accelerated periodic sources, search single pulses, as well interference-excision strategies candidate selection heuristics. This used to...
ABSTRACT We report the discovery of two long-term intermittent radio pulsars in ongoing Pulsar Arecibo L-Band Feed Array survey. Following with Telescope, extended observations these over several years at Jodrell Bank Observatory have revealed details their rotation and radiation properties. PSRs J1910+0517 J1929+1357 show extreme bimodal intermittency, switching between active (ON) inactive (OFF) emission states indicating presence a large, hitherto unrecognized underlying population such...
Einstein@Home aggregates the computer power of hundreds thousands volunteers from 193 countries, to search for new neutron stars using data electromagnetic and gravitational-wave detectors. This paper presents a detailed description radio pulsars Pulsar ALFA survey Arecibo Observatory. The enormous computing allows this cover region parameter space; it can detect in binary systems with orbital periods as short 11 minutes. We also describe first discovery, 40.8 Hz isolated pulsar PSR...
Einstein@Home, a distributed computing project, discovered rare, isolated pulsar with low magnetic field.
Modern radio pulsar surveys produce a large volume of prospective candidates, the majority which are polluted by human-created frequency interference or other forms noise. Typically, numbers candidates need to be visually inspected in order determine if they real pulsars. This process can labor intensive. In this paper, we introduce an algorithm called PEACE (Pulsar Evaluation Algorithm for Candidate Extraction) improves efficiency identifying signals. The ranks based on score function....
We present the discovery of five millisecond pulsars (MSPs) from PALFA Galactic plane survey using Arecibo. Four these (PSRs J0557+1551, J1850+0244, J1902+0300, and J1943+2210) are binary whose companions likely white dwarfs, one (PSR J1905+0453) is isolated. Phase-coherent timing solutions, ranging $\sim$1 to $\sim$3 years in length, based on observations Jodrell Bank Arecibo telescopes, provide precise determinations spin, orbital, astrometric parameters. All have large dispersion measures...
Abstract We present new discoveries and results from long-term timing of 72 pulsars discovered in the Pulsar Arecibo L -band Feed Array (PALFA) survey, including precise determination astrometric spin parameters, flux density scatter broadening measurements at 1.4 GHz. Notable include two young (characteristic ages ∼30 kyr) with no apparent supernova remnant associations, three mode-changing, 12 nulling intermittent pulsars. detected eight glitches five Among them is PSR J1939+2609, an...
For a uniform population of neutron stars whose spin-down is dominated by the emission gravitational radiation, an old argument Blandford states that expected gravitational-wave amplitude nearest source independent deformation and rotation frequency objects. Recent work has improved extended this to set upper limits on from also emit electromagnetic radiation. We restate these arguments in more general framework, simulate evolution such potential our galaxy. The simulations allow us test...
We have conducted a new search for radio pulsars in compact binary systems the Parkes multi-beam pulsar survey (PMPS) data, employing novel methods to remove Doppler modulation from motion. This has yielded unparalleled sensitivity binaries. The required computation time of ≈17, 000 CPU core years was provided by distributed volunteer computing project Einstein@Home, which sustained power about 1 PFlop s−1. discovered 24 our search, 18 were isolated pulsars, and 6 members systems. Despite...
We have made extensive observations of 35 distant slow (non-recycled) pulsars discovered in the ongoing Arecibo PALFA pulsar survey. Timing these over several years at Observatory and Jodrell Bank yielded high-precision positions measurements rotation properties. Despite being a relatively population, properties that mirror those previously known population. Many sources exhibit timing noise, one underwent small glitch. used multifrequency data to measure interstellar scattering pulsars....
Abstract In this paper, we present the results of timing observations PSRs J1949+3106 and J1950+2414, two binary millisecond pulsars (MSPs) discovered in data from Arecibo ALFA pulsar survey (PALFA). The parameters include precise measurements proper motions both pulsars, which show that PSR has a transversal motion very similar to an object local standard rest. also includes Shapiro delay rate advance periastron for systems. Assuming general relativity, these allow estimates masses...
We report on timing observations of the recently discovered binary pulsar PSR J1952+2630 using Arecibo Observatory. The mildly recycled 20.7-ms is in a 9.4-h orbit with massive, MWD > 0.93 M⊙, white dwarf (WD) companion. present, for first time, phase-coherent solution, precise spin, astrometric and Keplerian orbital parameters. This shows that characteristic age 77 Myr, younger by one order magnitude than any other pulsar–massive WD system. derive an upper limit true system 150 Myr....
We present two millisecond pulsar discoveries from the PALFA survey of Galactic plane with Arecibo telescope. PSR J1955+2527 is an isolated a period 4.87 ms, and J1949+3106 has 13.14 ms in 1.9 day binary system massive companion. Their timing solutions, based on 4 years measurements Arecibo, Green Bank, Nançay, Jodrell Bank telescopes, allow precise determination spin astrometric parameters, including determinations their proper motions. For J1949+3106, we can clearly detect Shapiro delay....
ABSTRACT We report on the discovery and timing observations of 29 distant long-period pulsars found in ongoing Arecibo L-band Feed Array pulsar survey. Following with Telescope, confirmation these over several years at Jodrell Bank Observatory have yielded high-precision positions measurements rotation radiation properties. used multi-frequency data to measure interstellar scattering properties some pulsars. Most that mirror those previously known population, although four show notable...
ABSTRACT We report the discovery and timing results for five millisecond pulsars (MSPs) from Arecibo PALFA survey: PSRs J1906+0055, J1914+0659, J1933+1726, J1938+2516, J1957+2516. Timing observations of were conducted with Lovell telescopes time spans ranging 1.5 to 3.3 years. All MSPs except one (PSR J1914+0659) are in binary systems low eccentricities. PSR J1957+2516 is likely a redback pulsar, <?CDATA $\sim 0.1\,{M}_{\odot }$?> companion possible eclipses that last ∼10% orbit. The...
We report the discovery of 20.7 ms binary pulsar J1952+2630, made using distributed computing project Einstein@Home in Pulsar ALFA survey observations with Arecibo telescope. Follow-up telescope confirm nature system. obtain a circular orbital solution an period 9.4 hr, projected radius 2.8 lt-s, and mass function f = 0.15 solar masses by analysis spin measurements. No evidence eccentricity is apparent; we set 2-sigma upper limit e < 1.7e-3. The parameters suggest massive white dwarf...
We report the discovery of millisecond pulsar (MSP) PSR J1950+2414 ($P=4.3$ ms) in a binary system with an eccentric ($e=0.08$) 22-day orbit Pulsar ALFA survey observations Arecibo telescope. Its companion star has median mass 0.3 $M_\odot$ and is most likely white dwarf. Fully recycled MSPs like this one are thought to be old neutron stars spun-up by transfer from star. This process should circularize orbit, as observed for vast majority MSPs, which predominantly have orbital eccentricities...
We present a Chandra X-ray survey of the disrupted recycled pulsars (DRPs), isolated radio with P > 20 ms and Bs < 3 × 1010 G. These observations were motivated as search for immediate descendants ≈10 central compact objects (CCOs) in supernova remnants (SNRs), which have similar timing magnetic properties DRPs, but are bright, thermal sources consistent minimal neutron star (NS) cooling curves. Since none DPRs detected this survey, there is no evidence that they "orphaned" CCOs, NSs whose...
The Pulsar Arecibo L-Band Feed Array (PALFA) survey, the most sensitive blind search for radio pulsars yet conducted, is ongoing at Observatory in Puerto Rico. vast majority of 180 discovered by PALFA have spin periods shorter than 2 seconds. surveys may miss long-period due to summing a finite number harmonic components conventional Fourier analyses (typically $\sim$16), or strong effect red noise low modulation frequencies. We address this reduction sensitivity using time-domain technique:...
We present the discovery and phase-coherent timing of four highly dispersed millisecond pulsars (MSPs) from Arecibo PALFA Galactic plane survey: PSRs J1844+0115, J1850+0124, J1900+0308, J1944+2236. Three are in binary systems with low-mass companions, which most likely white dwarfs, have orbital periods on order days. The fourth pulsar is isolated. All large dispersion measures (DM > 100 pc cm-3), distant (> 3.4 kpc), faint at 1.4 GHz (< 0.2 mJy), fully recycled (with spin P between...
We consider a simulated population of isolated Galactic neutron stars. The rotational frequency each star evolves through combination electromagnetic and gravitational wave emission. magnetic field strength dictates the dipolar emission, ellipticity (a measure star's deformation) Through both analytic numerical means, we assess detectability bound parameter space stars with or without direct detection. While our is primitive, this work establishes framework by which future efforts can be conducted.