Extending)the)sensi,vity)limits)of) VERA/KaVA)using...
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Extending the sensi,vity limits of VERA/KaVA using inverse phase referencing Ross Burns D3, Kagoshima University
Transcript of Extending)the)sensi,vity)limits)of) VERA/KaVA)using...
Extending the sensi,vity limits of VERA/KaVA using inverse phase
referencing
Ross Burns D3, Kagoshima University
Ross Burns D3, Kagoshima University
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Correlated flux density [Jy]
Why? Known QSOs (X-‐band)
Good ?
Normal limit
IPR – OK! There are more weak QSOs on the sky. IPR, use weak QSOs More reference sources available.
Ross Burns D3, Kagoshima University
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Correlated flux density [Jy]
Why? Known QSOs (X-‐band)
Good ?
Normal limit
IPR – OK! There are more weak QSOs on the sky. IPR, use weak QSOs More reference sources available.
B beam A beam Bright calibrator
Weak reference Φυ
A
Φ
IFs (frequency)
IFs (frequency)
Φ
frequency
(integrate channels) SPLIT
Maser
Φt
IMAGR All phase terms, ϕt, ϕν, are now solved
B-beam A-beam
FITLD and combine 15th IF channel FITLD
Amplitude and bandpass calibration
Amplitude and bandpass calibration
CVEL
TACOP
Apply delay-tracking solutions
FRING (delay and phase) usingthe bright calibrator (3C84)
SNCOR (IF 9)
SPLIT reference QSO(J0533+3451)
Apply delay-tracking solutions
TACOP
Dual-beam (instrumental)calibration
FRING maser (S235AB-MIR)
Phase and rate solutions for the reference maser
IMAGR IMAGR
AIPS
Special points • Maser must be near the phase tracking center
• Same IF bandwidth and freq. resolu,on in A and B beams
Center at RA 06 13 36.36007300 DEC 17 08 24.9454200
CONT: J0613+17 IPOL 22234.992 MHZ J0613+17.ICL001.1
Cont peak flux = 2.3230E-02 JY/BEAMLevs = 3.137E-03 * (-3, 3, 5, 7, 9, 11, 13, 15,17)
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Center at RA 06 13 36.36007300 DEC 17 08 24.9454200
CONT: J0613+17 IPOL 22234.992 MHZ J0613+17.ICL001.1
Cont peak flux = 3.8714E-02 JY/BEAMLevs = 1.831E-03 * (-3, 3, 5, 9, 13, 17, 21)
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Center at RA 06 13 36.36007300 DEC 17 08 24.9454200
CONT: J0613+17 IPOL 22234.992 MHZ J0613+17.ICL001.1
Cont peak flux = 2.3230E-02 JY/BEAMLevs = 3.137E-03 * (-3, 3, 5, 7, 9, 11, 13, 15,17)
Mill
iArc
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-25Center at RA 06 13 36.36007300 DEC 17 08 24.9454200
CONT: J0613+17 IPOL 22234.992 MHZ J0613+17.ICL001.1
Cont peak flux = 3.8714E-02 JY/BEAMLevs = 1.831E-03 * (-3, 3, 5, 9, 13, 17, 21)
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29 IFs 15 IFs
Merits of IPR • Can use weak quasars (detec,on / non-‐detec,on)
More available QSOs Some masers are ONLY near weak QSOs Effec,vely, VERA is more sensi,ve
• Typically get more masers in final images Maser maps are effec,vely self-‐calibrated, without
loosing absolute astrometry. (Also, don’t lose masers due to coherence loss during phase referencing)
• Faster!! * Time for FRING is a few seconds
* Aher re-‐making “UVW tables”
Recent results: S235AB-‐MIR
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Year
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Feature B
Feature A
R.A.
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Dec.
Dec.
Center at RA 05 33 12.76510000 DEC 34 51 30.3370000
CONT: J0533+34 IPOL 22217.992 MHZ J0533+34.ICL001.2
Cont peak flux = 1.5208E-02 JY/BEAMLevs = 8.357E-04 * (-3, 3, 5, 7, 9, 11, 13, 15,17)
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QSO; J0533+3451 F<20 mJy SNR 18
Recent results: S235AB-‐MIR
Recent results: S255 (IC2162)
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t (mas)
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offse
t (mas)
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2009 2010 2011
Offse
t (mas)
YearR.A. offset (mas)
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offse
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Center at RA 06 13 36.36007300 DEC 17 08 24.9454200
CONT: J0613+17 IPOL 22234.992 MHZ J0613+17.ICL001.1
Cont peak flux = 3.8714E-02 JY/BEAMLevs = 1.831E-03 * (-3, 3, 5, 9, 13, 17, 21)
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QSO; J0613+17 F<40 mJy SNR 22
Recent results: S255 (IC2162)
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Decl. offset (mas)
R.A. offset (mas)
1 mas/yr
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LSR velocity (km/s)
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1 mas/yr
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LSR velocity (km/s)
See poster!!
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Decl. offset (mas)
R.A. offset (mas)
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2014 2015
Offset (mas)
Year
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2014 2015
Offset (mas)
Year
Center at RA 05 33 12.76511100 DEC 34 51 30.3370100
CONT: J0533+34 IPOL 22233.992 MHZ J0533+34.ICL001.3
Cont peak !ux = 1.4622E-02 JY/BEAMLevs = 1.062E-03 * (-3, 3, 5, 7, 9, 11, 13, 15)
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Recent results: IRAS 05358 – by Mizukubo Kohei
See poster by K. Mizukubo !!
Inverse phase referencing AIPS POPS scripts
Full scripts are available on my website:
hvp://milkyway.sci.kagoshima-‐u.ac.jp/∼rossburns88/Scripts.html
Thanks for listening !!
