Presentation is loading. Please wait.

Presentation is loading. Please wait.

S3 time domain known pulsar search

Published byGinger Holt Modified over 5 years ago

Similar presentations

Presentation on theme: "S3 time domain known pulsar search"— Presentation transcript:

1 S3 time domain known pulsar search
Rejean Dupuis, Matthew Pitkin and Graham Woan for the LSC LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

2 LSC meeting, Univ. of Michigan
The story so far … We have previously been searching for known isolated pulsars with frequencies > 25 Hz (GW freq > 50 Hz) S2 produced upper limits for gravitational wave amplitude and neutron star ellipticity from 28 pulsars (PRL, 2005) We know the positions and spin-down parameters of these objects well from radio observations However there are more pulsars (82) with freqs > 25 Hz, most within binary systems … LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

3 LSC meeting, Univ. of Michigan
Pulsars f > 25 Hz J C J J J J J D J J J A J J E J A J J C J J F J J J J J G J J J J J H J J J J J I J J A J J J J J J B J J J L J J J A J J M J A J A J J D J N J J B J J E J O J J C J J F J P J J D J J G J Q J J E J J H J R J J F J J J S J J J A J C J T J J J B J A J U J J J C J B J V J J J D J J W J J J E J J J A J J J J J B J J J Preliminary S3 results (74) Awaiting timing data (36) For S3 the main change has been adding code to take account of Doppler shifts in the binary systems LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

4 LSC meeting, Univ. of Michigan
Binary pulsar signal In a binary system we need to take account of the pulsar motion within that system This adds extra terms to timing equivalent to those for the solar system These time delays are parameterised by various measurable properties of the binary system (period P, eccentricity e, angular velocity w, time of periastron T, projected semi-major axis asini etc) There are also other (model dependent) relativistic parameters Aberration delay (caused by pulsar rotation) Roemer deley (light travel time) LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

5 LSC meeting, Univ. of Michigan
Binary pulsar models 70 binary pulsars fall mainly into two model categories 32 ELL1 (low eccentricity) 33 BT (Blandford-Teukolsky) 1 BT2P (two orbiting planets) 4 DD (Damour-Deruelle) including double pulsar binary J A We have orbital parameters solutions over S3 for the majority of these pulsars from Andrew Lyne and Michael Kramer, Jodrell Bank. LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

6 Pulsar 11 – model and heterodyned output
Code testing Code has been written to calculate time delay with the three models BT, ELL1 and DD As we did for the solar system barycentring code, we have checked this against TEMPO Code has been tested against radio pulsar data with good agreement Two binary pulsars injected into end of S4 have been successfully extracted LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z Pulsar 10

7 LSC meeting, Univ. of Michigan
Analysis Analysis proceeds as for S2: Heterodyne to remove Doppler/spindown effects (including binary parameters where needed) Joint Bayesian analysis for unknown pulsar parameters, h0, f0, y and cosi using data (of unknown variance) from three LIGO interferometers produce probability distribution functions for unknown parameters and marginalise to get 95% upper limit on h0 LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

8 LSC meeting, Univ. of Michigan
Preliminary Results h0 Pulsars 5e-25 < h0 < 1e-24 16 1e-24 < h0 < 5e-24 52 5e-24 < h0 < 1e-23 4 h0 > 1e-23 2 Proposed for Amaldi Ellipticity Pulsars 1e-6 < e < 5e-6 7 5e-6 < e < 1e-5 16 1e-5 < e < 1e-4 40 e > 1e-4 11 All values assume I = 1038 kgm2 and no error on distance LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

9 Selected preliminary results
Lowest h0 upper limit: PSR J B (fgw = Hz, dist = 2.15 kpc) h0 = 5.3e-25 Lowest ellipticity upper limit PSR J (fgw = Hz, dist = 0.25 kpc) e = 1.5e-06 Closest to spin-down upper limit Crab pulsar ~ 5 times greater than spin-down (fgw = 59.6 Hz, dist = 2.0 kpc) h0 = 6.5e-24, e = 3.5e-3 Assumes I = 1038 kgm2 Proposed for Amaldi Crab pulsar LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

10 LSC meeting, Univ. of Michigan
I-e plane Crab pulsar – 2.0 kpc We do not really know neutron stars’ moment of inertia – so far we’ve been using the canonical value. Rather than use the upper limit on h0 to set a limit on e we can instead use it as an upper limit on the quadrupole moment ,Ie. This can then be plotted on a I-e plane providing exclusion regions on both the moment of inertia and ellipticity. Moment of inertia Izz Proposed for Amaldi LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

11 LSC meeting, Univ. of Michigan
Pulsar 3 S3 injections 10 pulsar injections were performed in S3 over large range of signal amplitudes and parameters Injections have been recovered with the correct parameters (after calibration corrections) Proposed for Amaldi Pulsar 4 LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

12 S3 results - astrophysics
Whilst our upper limits for these pulsars are generally well above those permitted by spin-down constraints and neutron star equations-of-state they have some astrophysical interest. We provide the first direct upper limits on gravitational wave emission for 46 of the 74 pulsars, now including binaries. For the 25 globular cluster pulsars we provide the limits independent of the cluster dynamics. Our most stringent ellipticities (1.5e-6) are starting to reach into the range permitted by at least one exotic theory of neutron star structure (B. Owen, submitted to PRL). The Crab pulsar is nearing the spin-down upper limit (with a couple of others only ~100 times greater e.g. binary pulsar J A) Proposed for Amaldi LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

13 LSC meeting, Univ. of Michigan
Proposed for Amaldi Presentation of S3 LIGO results for 74 pulsars thoroughly check input files and parameters get more radio data to confirm binary code check on possible Crab glitch during S3 Presentation of S3 pulsar hardware injections results are now well understood  Present joint GEO analysis for fastest pulsars check that GEO adds to the analyses LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

14 LSC meeting, Univ. of Michigan
Future work Near term Complete final review of S3 results Perform S4 analysis coherent analysis with S3 (S2 as priors?) Long term Rewrite software for “real time” S5 analysis (or at least speed up/optimise the code a lot) LSC meeting, Univ. of Michigan 04/06/05 LIGO-G Z

Download ppt "S3 time domain known pulsar search"

Similar presentations

A walk through some statistic details of LSC results.

A walk through some statistic details of LSC results.
LIGO-G080190-00-Z Beating the spin-down limit on gravitational wave emission from the Crab pulsar Michael Landry LIGO Hanford Observatory for the LIGO.

LIGO-G Z Beating the spin-down limit on gravitational wave emission from the Crab pulsar Michael Landry LIGO Hanford Observatory for the LIGO.
Upper-limit on Sco X-1 S2 preliminary results C Messenger, V Re and A Vecchio on behalf of PULG LSC General Meeting LHO, 10 th – 13 th November 2003.

Upper-limit on Sco X-1 S2 preliminary results C Messenger, V Re and A Vecchio on behalf of PULG LSC General Meeting LHO, 10 th – 13 th November 2003.
LIGO-G030659-00-Z 1 S2/E10 pulsar injection analysis Réjean Dupuis University of Glasgow 13 November 2003 LSC Meeting, LHO.

LIGO-G Z 1 S2/E10 pulsar injection analysis Réjean Dupuis University of Glasgow 13 November 2003 LSC Meeting, LHO.
Discovery of a Highly Eccentric Binary Millisecond Pulsar in a Gamma-Ray- Detected Globular Cluster Megan DeCesar (UWM) In collaboration with Scott Ransom.

Discovery of a Highly Eccentric Binary Millisecond Pulsar in a Gamma-Ray- Detected Globular Cluster Megan DeCesar (UWM) In collaboration with Scott Ransom.
Pulsar Detection and Parameter Estimation with MCMC - Six Parameters Nelson Christensen Physics and Astronomy Carleton College GWDAW December 2003.

Pulsar Detection and Parameter Estimation with MCMC - Six Parameters Nelson Christensen Physics and Astronomy Carleton College GWDAW December 2003.
Searches for continuous gravitational waves with LIGO and GEO600 M. Landry for the LIGO Scientific Collaboration LIGO Hanford Observatory, Richland WA.

Searches for continuous gravitational waves with LIGO and GEO600 M. Landry for the LIGO Scientific Collaboration LIGO Hanford Observatory, Richland WA.
1 Hough transform Some Fourier basics: –Nyquist frequency: 1/2 , with  the difference between time samples. If signal is bandwidth limited below Nyquist.

1 Hough transform Some Fourier basics: –Nyquist frequency: 1/2 , with  the difference between time samples. If signal is bandwidth limited below Nyquist.
Binary stellar systems are interesting to study for many reasons. For example, most stars are members of binary systems, and so studies of binary systems.

Binary stellar systems are interesting to study for many reasons. For example, most stars are members of binary systems, and so studies of binary systems.
LIGO Status and Advanced LIGO Plans Barry C Barish OSTP 1-Dec-04.

LIGO Status and Advanced LIGO Plans Barry C Barish OSTP 1-Dec-04.
November 2, 2006LIGO / pulsar workshop1 How LIGO searches are affected by theory & astronomical observations Ben Owen.

November 2, 2006LIGO / pulsar workshop1 How LIGO searches are affected by theory & astronomical observations Ben Owen.
The search for continuous gravitational waves: analyses from LIGO’s second science run Michael Landry LIGO Hanford Observatory on behalf of the LIGO.

The search for continuous gravitational waves: analyses from LIGO’s second science run Michael Landry LIGO Hanford Observatory on behalf of the LIGO.
The Strongly Relativistic Double Pulsar and LISA Vicky Kalogera Physics & Astronomy Dept with Chunglee Kim (NU) Duncan Lorimer (Manchester)

The Strongly Relativistic Double Pulsar and LISA Vicky Kalogera Physics & Astronomy Dept with Chunglee Kim (NU) Duncan Lorimer (Manchester)
1 Known Isolated Pulsars Preliminary S2 Results Réjean Dupuis, Matt Pitkin, Graham Woan LIGO-G030584-00-Z.

1 Known Isolated Pulsars Preliminary S2 Results Réjean Dupuis, Matt Pitkin, Graham Woan LIGO-G Z.
CW signals: plans for S2 June 16-17 the group held a f2f meeting to discuss plans for analyses of S2 data (and beyond). Slides from the various presentations.

CW signals: plans for S2 June the group held a f2f meeting to discuss plans for analyses of S2 data (and beyond). Slides from the various presentations.
1/25 Current results and future scenarios for gravitational wave’s stochastic background G. Cella – INFN sez. Pisa.

1/25 Current results and future scenarios for gravitational wave’s stochastic background G. Cella – INFN sez. Pisa.
Neutron Star (Mostly Pulsar) Masses Ingrid Stairs UBC Vancouver CAWONAPS TRIUMF Dec. 9, 2010.

Neutron Star (Mostly Pulsar) Masses Ingrid Stairs UBC Vancouver CAWONAPS TRIUMF Dec. 9, 2010.
Acknowledgements The work presented in this poster was carried out within the LIGO Scientific Collaboration (LSC). The methods and results presented here.

Acknowledgements The work presented in this poster was carried out within the LIGO Scientific Collaboration (LSC). The methods and results presented here.
Alicia M. Sintes Universitat de les Illes Balears Paris,17 November 2006 Current searches for continuous gravitational waves.

Alicia M. Sintes Universitat de les Illes Balears Paris,17 November 2006 Current searches for continuous gravitational waves.
Searching for gravitational radiation from Scorpius X-1: Limits from the second LIGO science run Alberto Vecchio on behalf of the LIGO Scientific Collaboration.

Searching for gravitational radiation from Scorpius X-1: Limits from the second LIGO science run Alberto Vecchio on behalf of the LIGO Scientific Collaboration.

Similar presentations

Ads by Google