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Observation Date (UT) Observation Lat

Canonical Name:S5 0716+714
TeVCat Name:TeV J0721+713
Other Names:1H 0717+714
Source Type:IBL
R.A.:07 21 53.4 (hh mm ss)
Dec.:+71 20 36 (dd mm ss)
Gal Long: 143.98 (deg)
Gal Lat: 28.02 (deg)
Distance: z=0.31
Flux: (Crab Units)
Energy Threshold:0.4 GeV
Spectral Index:3.45
Extended:No
Discovery Date:2008-04
Discovered By: MAGIC
TeVCat SubCat:Default Catalog

Source Notes:

Source position and its uncertainty:
- no information is provided
- the position provided by NED is used

Distance:
From MAGIC Collaboration (2018):
- "The simultaneous spectra from MAGIC and Fermi-LAT were used to
estimate the redshift of the source. We apply the method presented in
Prandini et al. (2010, 2011) based on the assumption that the slope of
the VHE spectrum corrected for EBL absorption should not be harder
than the one measured by Fermi-LAT at lower energies"
- "The empirical formula proposed in Prandini et al. (2011) applied to
this data gives as most probable value for the redshift
z_rec = 0.31 +/- 0.02stat +/- 0.05sys, where the first error is
related to the statistical errors of Fermi-LAT and MAGIC slopes, while
the second error is the error of the method itself, as estimated in
Prandini et al. (2011)."
From Danforth et al. (2012):
- "... we set a statistical upper bound of z < 0.322 (95% confidence)
on the blazar. This is the first direct redshift limit for this object
and is consistent with literature estimates of z = 0.31 +/- 0.08 based
on the detection of a host galaxy."
From Mazin et al. (2009):
- "Due to the very bright nucleus, which outshines the host galaxy,
the redshift of S5 0716+714 is still uncertain"
From Nilsson et al. (2008):
- "We have acquired a deep i-band image of the BL Lacertae object S5
0716+714 while the target was in an low optical state. Due to the
faintness of the nucleus, we were able to detect the underlying host
galaxy. The host galaxy is measured to have an I-band magnitude of
17.5 +/- 0.5 and an effective radius of (2.7 +/- 0.8) arcsec. Using
the host galaxy as a “standard candle”, we derive z = 0.31 +/- 0.08
(1 sigma error) for the host galaxy of S5 0716+714. This redshift is
consistent with the redshift z = 0.26 determined by spectroscopy for 3
galaxies close to S5 0716+714. The effective radius at z = 0.31 would
be 12 +/- 4 kpc, which is consistent with values obtained for BL Lac
host galaxies. An optical spectrum acquired during the same epoch
shows no identifiable spectral lines."

Flux:
From MAGIC Collaboration (2018):
- "On 19 January 2015 (MJD 57041), triggered by the high optical state
and by high-energy photons detected by Fermi-LAT, MAGIC started to
observe S5 0716+714. On 23 January 2015 (MJD 57045) the significance
of the signal was found to be 6.4 sigma, and it reached a maximum
value of 13.2 sigma on 26 January (MJD 57048): the flux increased from
(4.1 +/- 1.1) 10e-11 cm-2 s-1 to (8.9 +/- 1.1) 10e-11 cm-2 s-1 above
150 GeV, which is the highest level ever detected in the VHE band for
this source. The next activity of S5 0716+714 in the VHE range was
detected by MAGIC on 13 February (MJD 57066), this time lasting four
days only, up to the 16 February (MJD 57069)."

Spectral Index:
From MAGIC Collaboration (2018):
- "In the present work the two multi-wavelength periods of
observations that include MAGIC data are indicated as Phase A, from 18
to 27 January 2015 (MJD 57040 to MJD 57050), and Phase B from 12 to 17
February 2015 (MJD 57065 to MJD 57070)."
- During Phase A (MJD 57040-57050): observed spectral index: 4.08 +/- 0.22 (stat) +/- 0.15 (syst)
- During Phase A (MJD 57040-57050): intrinsic spectral index: 2.73 +/- 0.28 (stat) +/- 0.15 (syst)
- During Phase B (MJD 57065-57070): observed spectral index: 4.64 +/- 0.49 (stat) +/- 0.15 (syst)
- During Phase B (): observed spectral index: 3.65 +/- 0.53 (stat) +/- 0.15 (syst)
From Anderhub et al. (2009):
- 3.45 +/- 0.54(stat) +/- 0.2(syst)

Classification:
Initially, this source was classified as an LBL in TeVCat. It has
been updated (121113) to an IBL based on its classification in
the Fermi 2nd AGN Catalog (Ackermann et al. 2012)


Seen by: MAGIC
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