Einstein@Home Gamma-ray Pulsar Discoveries in Fermi-LAT Data
Info
Einstein@Home searches data from NASA's Fermi Gamma-ray Space Telescope for signals from
gamma-ray pulsars. Pulsars are very compact stars with extreme physical properties compared to normal matter.
They are rapidly spinning neutron stars that emit pulses, observable from radio to
gamma-ray wavelengths.
Searching for new pulsars is an enormous computational challenge, because their spin
frequencies, sky position and other parameters are unknown. Thus, this requires a blind
search, where one explicitly searches over a dense grid in parameter space. However, the
number of discrete grid points to cover such multi-dimensional parameter spaces is
tremendous and renders "brute forces approaches" computationally unfeasible.
We have developed novel and much more efficient data-analysis methods for the volunteer
supercomputer Einstein@Home, which ranks among the fastest 25 computer systems worldwide.
Einstein@Home has now discovered four new gamma-ray pulsars that were previously
inaccessible on computational grounds.
These radio and gamma-ray pulsar discoveries provide important contributions to advance
our (yet very poor) understanding these stellar objects, their population, and their role
in our Universe.
New Einstein@Home gamma-ray pulsar discoveries
This page contains information about the Einstein@Home gamma-ray pulsar discoveries. For
each pulsar we list the volunteers whose computers discovered the pulsar, and the date at
which the pulsar was found.
The plots on the right show the pulse profile of each pulsar in green, and the phase-folded
arrival times of all the gamma-ray photons on the far right. These plots require precise
knowledge of the pulsar sky position, its spin frequency, and spin frequency derivative.
Using these, each photon can be assigned a rotational phase, i.e., in which direction the
pulsar was pointing when the gamma-ray photon was emitted. Thus, we can reconstruct the
gamma-ray emission as a function of pulsar rotation phase and resolve the pulse profile.
We also provide a list of selected characteristics for each
of the pulsars. Right ascension is one of the two celestial coordinates that specify the
sky position of the pulsar. Declination is the second of these. The spin frequency describes
how many time per second the pulsar is rotating. The first frequency derivative describes
how much the pulsar is slowing down over time. The energy required to emit electromagnetic
radiation is drawn from the pulsar rotation. The characteristic age is a rough estimate of
the pulsar's age, computed from the spin frequency and its derivative. Finally, the
spin-down power is a measure of the total energy emitted by the pulsar. For comparison, our
Sun outputs roughly 4 x 1033 erg per second. All pulsars below have a much higher
spin-down power.
Update: Pulsar Discoveries from FGRP4
In August 2014, we began the 4th Einstein@Home survey for gamma-ray pulsars, or
"FGRP4". This survey incorporated many new advances that we learned during our previous
investigation of blind search methods. In addition, we were able to utilised the superior "Pass 8"
data from the Fermi-LAT team, and search in longer data sets than ever before. In
combination, these improvements led to FGRP4 being our most sensitive survey to date.
We are very pleased to be able to announce the first set of results from FGRP4. Including the
discovery of PSR J1906+0722 at the beginning of this survey, these bring the total number of
gamma-ray pulsars discovered by our Einstein@Home volunteers to 18. You can find the details and
plots of all the new discoveries below!
Currently we are working very hard to study all of the results from FGRP4, and we are hoping to
present these in a series of papers in the near future.
As always, we are extremely grateful to all of our volunteers, especially those whose computers
contributed to these new discoveries. To say "we couldn't have done it without you!" would be a terrible
understatement!
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Volunteers (Country):
UW-Madison CAE (USA) and RUElwell (USA)
Date:
31 Dec 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 00:02
Declination: +62:16
Spin frequency: 8.67 Hz
First frequency derivate: -4.48 x 10-13 Hz/s
Characteristic age: 306.3 kyrs
Spin-down power: 1.5 x 1035 erg/s
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Volunteers (Country):
ATLAS AEI Hannover (Germany) and Delty (USA)
Date:
15 Dec 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 03:59
Declination: +54:14
Spin frequency: 12.59 Hz
First frequency derivate: -2.65 x 10-12 Hz/s
Characteristic age: 75.2 kyrs
Spin-down power: 1.3 x 1036 erg/s
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Volunteers (Country):
David Z (Canada) and Test (France)
Date:
06 Jan 2012
Survey:
FGRP1
Selected pulsar parameters:
Right ascension: 05:54:05.01(3)
Declination: +31:07:41(4)
Spin frequency: 2.15 Hz
First frequency derivate: -0.66 x 10-12 Hz/s
Characteristic age: 51.7 kyrs
Spin-down power: 5.6 x 1034 erg/s
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Volunteers (Country):
KataJun (Japan) and huwar
Date:
20 Jan 2015
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 06:31
Declination: +06:46
Spin frequency: 9.01 Hz
First frequency derivate: -2.94 x 10-13 Hz/s
Characteristic age: 486.1 kyrs
Spin-down power: 1.0 x 1035 erg/s
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Volunteers (Country):
Syracuse University (USA) and LLO_LDAS (USA)
Date:
28 Oct 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 10:57
Declination: -58:51
Spin frequency: 1.61 Hz
First frequency derivate: -2.61 x 10-13 Hz/s
Characteristic age: 97.7 kyrs
Spin-down power: 1.7 x 1034 erg/s
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Volunteers (Country):
ATLAS AEI Hannover (Germany) and Syracuse University (USA)
Date:
03 Oct 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 11:05
Declination: -60:37
Spin frequency: 5.13 Hz
First frequency derivate: -5.75 x 10-13 Hz/s
Characteristic age: 141.4 kyrs
Spin-down power: 1.2 x 1035 erg/s
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Volunteers (Country):
PeRu (Czech Republic) and Bryden Kanngiesser (Canada)
Date:
19 Jun 2015
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 13:50
Declination: -62:25
Spin frequency: 7.24 Hz
First frequency derivate: -4.65 x 10-13 Hz/s
Characteristic age: 246.4 kyrs
Spin-down power: 1.3 x 1035 erg/s
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Volunteers (Country):
Mak-ino (Japan) and Thomas M. Jackson (USA)
Date:
14 Dec 2011
Survey:
FGRP1
Selected pulsar parameters:
Right ascension: 14:22:27.07(1)
Declination: -61:38:28(1)
Spin frequency: 2.93 Hz
First frequency derivate: -0.83 x 10-12 Hz/s
Characteristic age: 55.8 kyrs
Spin-down power: 9.6 x 1034 erg/s
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Volunteers (Country):
The NEMO computing cluster (USA) and Chen (USA)
Date:
30 Sep 2011
Survey:
FGRP1
Selected pulsar parameters:
Right ascension: 15:22:05.3(1)
Declination: -57:35:00(1)
Spin frequency: 9.79 Hz
First frequency derivate: -2.99 x 10-12 Hz/s
Characteristic age: 51.8 kyrs
Spin-down power: 115.7 x 1034 erg/s
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Volunteers (Country):
fred c (USA) and Gabriel Vasquez
Date:
25 Mar 2015
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 15:28
Declination: -58:38
Spin frequency: 2.81 Hz
First frequency derivate: -1.96 x 10-13 Hz/s
Characteristic age: 227.6 kyrs
Spin-down power: 2.2 x 1034 erg/s
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Volunteers (Country):
r4p and Greg Dorais (USA)
Date:
04 Oct 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 16:23
Declination: -50:05
Spin frequency: 11.75 Hz
First frequency derivate: -5.75 x 10-13 Hz/s
Characteristic age: 323.9 kyrs
Spin-down power: 2.7 x 1035 erg/s
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Volunteers (Country):
xio.nyc (Antarctica) and Hung Tran (USA)
Date:
20 Dec 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 16:24
Declination: -40:41
Spin frequency: 5.96 Hz
First frequency derivate: -1.68 x 10-13 Hz/s
Characteristic age: 562.9 kyrs
Spin-down power: 3.9 x 1034 erg/s
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Volunteers (Country):
Syracuse University (USA) and Eric Schwartz (USA)
Date:
17 Oct 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 16:50
Declination: -46:01
Spin frequency: 7.87 Hz
First frequency derivate: -9.37 x 10-13 Hz/s
Characteristic age: 133.0 kyrs
Spin-down power: 2.9 x 1035 erg/s
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Volunteers (Country):
ATLAS AEI Hannover (Germany) and LLO_LDAS (USA)
Date:
19 Dec 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 18:27
Declination: -14:46
Spin frequency: 2.00 Hz
First frequency derivate: -1.82 x 10-13 Hz/s
Characteristic age: 174.5 kyrs
Spin-down power: 1.4 x 1034 erg/s
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Volunteers (Country):
Aurelien FAUCHEUX (France) and Roger (USA)
Date:
18 Nov 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 18:44
Declination: -03:46
Spin frequency: 8.86 Hz
First frequency derivate: -1.21 x 10-11 Hz/s
Characteristic age: 11.6 kyrs
Spin-down power: 4.2 x 1036 erg/s
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Volunteers (Country):
Connor Barry (USA) and Richard Johnson (USA)
Date:
11 Sep 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 19:06:31.20(1)
Declination: +07:22:55.8(4)
Spin frequency: 8.97 Hz
First frequency derivate: -2.88 x 10-12 Hz/s
Characteristic age: 49.2 kyrs
Spin-down power: 1.02 x 1036 erg/s
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Volunteers (Country):
Doug Lean (Australia) and Hans-Peter Tobler (Germany)
Date:
19 Sep 2011
Survey:
FGRP1
Selected pulsar parameters:
Right ascension: 19:32:19.70(4)
Declination: +19:16:39(1)
Spin frequency: 4.80 Hz
First frequency derivate: -2.15 x 10-12 Hz/s
Characteristic age: 35.4 kyrs
Spin-down power: 40.7 x 1034 erg/s
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Volunteers (Country):
gramoll (USA) and Rogir (Germany)
Date:
09 Sep 2014
Survey:
FGRP4
Selected pulsar parameters:
Right ascension: 20:17
Declination: +36:25
Spin frequency: 6.00 Hz
First frequency derivate: -4.89 x 10-14 Hz/s
Characteristic age: 1942.8 kyrs
Spin-down power: 1.2 x 1034 erg/s
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