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MAGIC pulsar workshop, Padova, Feb 2010
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Pulsar Timing Analysis
MAGIC pulsar workshop, Padova, Feb 2010
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/hadron separation (I)
Different kind primary particles different showers different images /hadron separation based on image parameter distributions -images are smaller and point to camera center Hadron showers are broader are randomly oriented MAGIC pulsar workshop, Padova, Feb 2010
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/hadron separation (II)
After applying /hadron cuts based on image shape, exploit shower direction MAGIC pulsar workshop, Padova, Feb 2010
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Timing analysis Goal: Find the periodic signal of the pulsar, hidden in the arrival times of the atmospheric showers The timing analysis involves 4 steps: Barycenter correction Obtain the Light curve Application of Uniformity test Upper limits calculation All these steps have been implemented in a dedicated software, for the pulsar Analysis in MAGIC MAGIC pulsar workshop, Padova, Feb 2010
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Timing analysis (I) Barycenter correction
Remove the effect of the earth movement on the arrival times tUTC. Transform the measured arrival times to the Solar System Barycenter: Total Barycenter correction MAGIC pulsar workshop, Padova, Feb 2010
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Timing analysis (II) Ligth curve
If F is the known rotational frequency of the pulsar at time T0, the number of revolutions in dt=t-T0 is: Integrating, and taking the fractional part, we get the rotational phase : where t is the barycenter time Taylor MAGIC pulsar workshop, Padova, Feb 2010
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Timing analysis (III) Crab is “glitching” once every 3-6 years !
Ephemeris are usually taken from radio observations but affected by irregularities in pulsar rotation: Timing noise Glitches Crab pulsar Crab is “glitching” once every 3-6 years ! Need to have contemporaneous ephemeris We use monthly ephemeris by Jodrell Bank MAGIC pulsar workshop, Padova, Feb 2010
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Timing analysis (III) Uniformity tests
If no periodicity events will be uniformly distributed ² - test Applied to k-bins histograms Powerful test for narrow pulses Probability follows a 2 of k-1 d.o.f Zm2-test Independent of k Based on trigonometric moments of pulse profile m=number of harmonics Sensitive to narrower pulses as m increases H test Find optimal m Powerful against a large variety of light curves MAGIC pulsar workshop, Padova, Feb 2010
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MAGIC Timing Analysis Toolkit
Developed a full pulsar analysis toolkit for MAGIC You can do all you need, both for optical & gamma-ray data Input files can be ascii, raw or root files: Extract Central Pixel signal Do barycenter correction Search best ephemeris for each arrival time Calc pulsar phase & create light curves Apply periodicity tests And moreover.. Apply cuts Calc. collection areas Calc. upper limits Calc. spectrum MAGIC pulsar workshop, Padova, Feb 2010
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MAGIC Timing Analysis Toolkit
Code at MARS/mtemp/mucm/mpulsar More that lines of code Manual at: MARS/mtemp/mucm/mpulsar/docmpulsar.pdf MAGIC pulsar workshop, Padova, Feb 2010
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MAGIC Timing Analysis Toolkit
How to compile it Compile the classes adding the following lines to the Makefile: SUBDIRS = manalysis \ mastro \ … mtemp/mucm/classes \ mtemp/mucm/pulsar Compile the SearchPeriod program PROGRAMS = callisto celestina … SearchPeriod MAGIC pulsar workshop, Padova, Feb 2010
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MAGIC Timing Analysis Toolkit
Main Classes MAGIC pulsar workshop, Padova, Feb 2010
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MAGIC Timing Analysis Toolkit
How to use it You can use the classes writing your our macro. E.g.: mtemp/mucm/mpulsar/macros Or using the compiled program SearchPeriod (similar to callisto,..) It has a basic GUI (search.tcl) MAGIC pulsar workshop, Padova, Feb 2010
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MAGIC Timing Analysis Toolkit
Tests Toolkit tested on: Crab optical signal EGRET data XMM data Results checked against TEMPO MAGIC pulsar workshop, Padova, Feb 2010
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