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The MAGIC telescopes have observed an increase in the Very High Energy (VHE ; >100 GeV) gamma-ray flux from PKS 1510-089 (RA=15 12 50.5, Dec=-09 06 00, J2000.0). The preliminary analysis of the MAGIC data taken from 2015/05/18 to 2015/05/19 shows a highly significant signal and a flux of ~20% from that of the Crab nebula above 100 GeV. This implies an increase by a factor of ~5 with respect to the flux reported previously in 2012. PKS 1510-089 is a FSRQ at z=0.36 and it is regularly monitored by MAGIC. The source is also active in the high energy gamma-ray band as seen by Fermi-LAT ( http://fermi.gsfc.nasa.gov/ssc/data/access/lat/msl_lc/source/1510-089 ), and in optical band as reported by the Tuorla blazar monitoring program (http://users.utu.fi/kani/1m, R=14.75 on 2015/05/19). ATels #7495 and #7466 also report an increase in the IR brightness. We have also triggered ToO observations with the Swift satellite, which did not show any substantial enhancement in the X-ray flux (http://www.swift.psu.edu/monitoring/source.php?source=PKS1510-089). MAGIC observations on PKS1510-089 will continue during the following nights, and multi-wavelength observations are encouraged. The MAGIC contact persons for these observations are R. Mirzoyan (Razmik.Mirzoyan@mpp.mpg.de) and E. Lindfors (elilin@utu.fi). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The blazar S5 0716+714 was recently reported to be at exceptionally high optical state (ATel#6902, ATel#6942, ATel#6944, ATel#6953, ATel#6957), which triggered MAGIC observations of the source in very high energy gamma rays (VHE, E>100 GeV). The preliminary analysis of the MAGIC data taken between 2015/01/22 and 2015/01/26 indicates potentially variable VHE flux in the range from 4x10^-11 cm^-2 s^-1 to 7x10^-11 cm^-2 s^-1 above 150GeV. S5 0716+714 is a blazar with z~0.31 (Nilsson et al. 2008, A&A...487L..29N), which was reported as VHE emitter in 2008 (Anderhub et al. 2009, ApJ, 704, 129). The measured integral flux above 400 GeV was (7.5 +- 2.2) * 10^-12 cm^-2 s^-1. The 2008 detection is the only significant detection of VHE gamma-ray emission prior to observations reported here. Notably, the 2008 MAGIC detection of the source took place during a high optical state, too. The MAGIC observations were accompanied with simultaneous optical observations with the KVA telescope. The R-band magnitude on 2015/01/26 was 11.84, the lightcurve is available at: http://users.utu.fi/kani/1m/S5_0716+714.html MAGIC observations on S5 0716+714 will continue for one more night and multiwavelength observations are encouraged. The MAGIC contact persons for these observations are R. Mirzoyan (Razmik.Mirzoyan@mpp.mpg.de) and E. Lindfors (elilin@utu.fi). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC collaboration reports the discovery of very high energy (VHE ; E>100 GeV) gamma-ray emission from the FSRQ S4 0954+65 (RA=+9:58:47.00, DEC=+65:33:55.00, J2000.0), located at redshift z=0.368. The object was observed with the MAGIC telescopes for ~2 hours during the night 2015 February 13/14 (MJD 57067). A preliminary analysis of the data yields detection with a statistical significance of more than 5 standard deviations. This is the first time a significant signal at VHE gamma rays has been seen from S4 0954+65. The flux above 150GeV is estimated to be about 2e-11 cm^-2 s^-1. S4 0954+65 is entered an exceptionally high state at optical and near infrared frequencies (ATels #7057 ; #7055 ; #7046, #7001 ; #6996), which triggered the MAGIC observations. Optical observations performed with the KVA telescope suggests that this is the brightest state ever observed from this source since November 2006 (beginning of KVA observations). The preliminary lightcurve is available at: http://users.utu.fi/kani/1m/S4_0954+65.html. During the preparation of this ATel, we were informed by Fermi-LAT collaboration that the gamma-ray flux above 100 MeV from S4 0954+65 also increased substantially during the last few days. MAGIC observations on S4 0954+65 will continue during the following nights, and multiwavelength observations are encouraged. The MAGIC contact persons for these observations are R. Mirzoyan (Razmik.Mirzoyan@mpp.mpg.de) and E. Lindfors (elilin@utu.fi). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC telescopes have detected an increase in the Very High Energy (VHE ; >100 GeV) gamma-ray flux from BL Lacertae (RA=22h02m43.3s Dec=+42d16m40s, J2000.0). The preliminary analysis of the MAGIC data taken from 2015/06/14 to 2015/06/17 indicates a highly significant signal above 200 GeV. The emission is variable, with a flux of 0.4 and 0.1 times the flux of the Crab nebula above 200 GeV in the nights 14/15 and 16/17, respectively. MAGIC telescopes observed BL Lacertae in 3 consecutive nights for duration of 1 hour per night, under excellent weather conditions. In the night of 15/16 June there was no detection. The flux level is similar to the flaring state reported in Arlen et al. 2013. In the low state the source is typically not detectable with IACTs. The MAGIC observations were triggered by the high activity measured at optical and gamma-ray energies. The source is active in the high energy gamma-ray band as seen by Fermi-LAT (http://fermi.gsfc.nasa.gov/ssc/data/access/lat/msl_lc/source/BL_Lac), and in optical band as reported by Tuorla blazar monitoring program (http://users.utu.fi/kani/1m/BL_Lac.html). We have also triggered ToO observations with the Swift satellite, which did not show any substantial enhancement in the X-ray flux (http://www.swift.psu.edu/monitoring/source.php?source=BLLacertae). MAGIC observations on BL Lacertae will continue during the following nights, and multiwavelength observations are encouraged. The MAGIC contact persons for these observations are R. Mirzoyan (Razmik.Mirzoyan@mpp.mpg.de) and D. Dominis Prester (dijana@phy.uniri.hr). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC collaboration reports the discovery of very high energy (VHE ; E>100 GeV) gamma-ray emission from the FSRQ PKS 1441+25 (RA=14h43m56.9s DEC=+25d01m44s), located at redshift z=0.939 (Shaw et al. 2012, ApJ, 748, 49). The object was observed with the MAGIC telescopes for ~2 hours during the night 2015 April 17/18, and for ~4 hours during 18/19. A preliminary analysis of the data yields a detection with a statistical significance of more than 6 standard deviations for the night of April 17/18, and more than 11 standard deviations for 18/19. This is the first time a significant signal at VHE gamma rays has been seen from PKS 1441+25. The flux above 80 GeV is estimated to be about 8e-11 cm^-2 s^-1 (16% of Crab Nebula flux). PKS 1441+25 has entered an exceptionally high state at optical, X-, and Gamma-ray frequencies (ATel #7402), which triggered the MAGIC observations. The Swift Follow-up observation from April 18/19 revealed that the high state in X-rays is continuing: http://www.swift.psu.edu/monitoring/source.php?source=PKS1441+25 MAGIC observations on PKS1441+25 will continue during the following nights, and multiwavelength observations are encouraged. The MAGIC contact persons for these observations are R. Mirzoyan (Razmik.Mirzoyan@mpp.mpg.de) and E. Lindfors (elilin@utu.fi). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC collaboration reports the discovery of very high energy (VHE ; E>100 GeV) gamma-ray emission from the BL Lac S2 0109+22 (RA: 01h12m05.8s Dec:+22d44m39s, J2000). The object was observed with the MAGIC telescopes for 5.3 hours from 2015/07/22 to 2015/07/25, following the high-flux state spotted in the high-energy (E>10 GeV) domain of the public Fermi/LAT data, according to the prescription of Pacciani et al. ApJ 790 (2014) 45. The preliminary analysis of the first three nights of MAGIC data showed an excess with a statistical significance of ~5 standard deviations. The VHE flux of this detection was estimated to be (1.6+/-0.7)e-11 ph/cm2/s above 100 GeV, about 3% of the flux from the Crab nebula. The daily flux shows a marked enhancement on the night of 25 July up to (9.7+/-1.5)e-11 ph/cm2/s, ~15% of the Crab flux at E>100 GeV, corresponding to an excess with >7 sigma statistical significance. S2 0109+22 is located at the red shift z=0.265 (from CGRaBS spectroscopy, Healey et al., ApJ 175 (2008) 97). It is classified as an intermediate-synchrotron peaked BL Lac object in the 2LAC (Ackermann et al. ApJ 743 (2011) 171). The multi-year optical and radio historical coverage (Ciprini et al. MNRAS 348 (2004) 1379) showed optical variations with typical timescales from weeks to months. The Fermi/LAT flaring activity triggered a ToO observation with Swift, started on 2015/07/21. The preliminary Swift/XRT analysis showed an unabsorbed flux (7.0+-0.3)E-12 erg/cm2/s in the 0.3-10 keV range. From archival Swift/XRT data the brightest state previously observed had a flux (2.5+-0.3)E-12 erg/cm2/s. This corresponds to a 2-3 fold flux enhancement in X-rays. Instead the optical (UV) flux is ~50% (~30%) lower than at the brightest state observed with Swift/UVOT. MAGIC observations on S2 0109+22 will continue during the next days until July 28 and multi-wavelength observations are encouraged. The MAGIC contact persons for these observations are A. Stamerra (INAF-SNS, stamerra@oato.inaf.it) and R. Mirzoyan (MPI, Razmik.Mirzoyan@mpp.mpg.de) MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC collaboration reports the discovery of very high energy (VHE ; E>100 GeV) gamma-ray emission from RX J1136.5+6737 (a.k.a. RBS 1004) (RA: 11:36:30.1 DEC: +67:37:04, J2000) at redshift z=0.1342. RX J1136.5+6737 is an X-ray bright high-peaked frequency BL Lac object as listed in the MAXI 3-year catalog (Hiroi et al. 2013), which includes 13 BL Lacs (all HBLs and 9 TeV HBLs). The source has also been detected by Fermi-LAT, in the Second Fermi-LAT source catalog (2FGL ; Nolan et al. 2012) with a hard photon index 1.68+/-0.12, and belongs to the first Fermi-LAT catalog of >10 GeV sources (1FHL ; Ackermann et al, 2013), showing bright (photon flux = 11.7e-11 ph cm^-2 s^-1) emission above 10 GeV, and identified as a good candidate for VHE detection. RX J1136.5+6737 was observed with the MAGIC telescopes starting on 2014 January 29. Data taken up to 2014 April 3 (about 20 hours in total) yielded a source detection with a statistical significance of more than 5 standard deviations. The averaged flux measured by MAGIC during the 2014 observations corresponded to about 1.5% of the Crab nebula at energies above 200 GeV. MAGIC is planning to resume observations of the source on April 18th (right after the full-moon break). Multi-wavelength observations are encouraged.

The MAGIC collaboration reports the discovery of very high energy (VHE ; E>100 GeV) gamma-ray emission from RBS 0723 (RA: 08:47:12.9 DEC: +11:33:50, J2000.0) RBS 0723 is a BL Lac object at redshift z=0.198. The source has been detected by Fermi-LAT, in the Second Fermi-LAT source Catalogue (2FGL ; Nolan et al. 2012) with F(>1 GeV) = (5.3+-1.2)e-10 cm^-2 s^-1 and with photon index 1.48+-0.16. It also belongs to the first Fermi-LAT catalog of >10 GeV sources (1FHL ; Ackermann et al, 2013), showing a hard (photon index = 1.4 +- 0.4) and bright (photon flux = 9.6e-11 ph cm^-2 s^-1) emission above 10 GeV, and identified as a good candidate for VHE detection. The shape of the SED indicates it is one of the subclass of the extreme HBL characterized by extremely hard X-ray and VHE continua. RBS 0723 was observed starting on 2013 December 3. Data taken between 2014 Jan 1 and Jan 8 (about 10 hours) yields a source detection with a statistical significance of more than 5 standard deviations. The non-detection in the earlier data taken in 2013 Dec. suggests VHE flux variability. The VHE emission measured with MAGIC has a flux of about 2.5% of the Crab nebula at energies above 200 GeV. Optical monitoring with KVA telescope (La Palma) also shows evidence of an increased flux (R=17.2 in December 2013, R=16.9 in January 2014). MAGIC observations of RBS 0723 will resume on Jan. 22. Multi-wavelength observations are encouraged. The MAGIC contact persons for these observations are R. Mirzoyan (razmik.mirzoyan@mpp.mpg.de) and F. Tavecchio (fabrizio.tavecchio@brera.inaf.it). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC collaboration observed SN2014J, the nearest supernova (SN) explosion in 10 years, located in the galaxy M82. The MAGIC observations started 6 days after the first detection by the UCL Observatory (CBET #3792) and amounted to a total of 5.4 hours. This Ia-type SN is unique and follow-up observations in all wavelengths have been pursued (i.e. ATel #5835, #5809, #5812, #5851). The SN was observed with the MAGIC telescopes from January 27 to 29 under moderate moonlight conditions and on February 1 and 2 under dark-night conditions. The preliminary analysis of these data resulted in an integral flux upper limit of 1.6e-12 cm-2 s-1 above the energy 300 GeV at 95% c.l. (this corresponds to ~1.3% of the Crab Nebula flux ; for energies above 700 GeV the corresponding limit is ~2%), assuming a Crab-like spectral index. The daily flux upper limits (~1h observation per day) vary from 1.8e-12 to 18.e-12 cm-2 s-1 (E>300 GeV, 95% c.l.), due to different observational conditions. The VHE flux contribution from the host galaxy M82 was previously measured by VERITAS (Nature, 462, 700) at the level of 0.9% of the Crab flux for E>700 GeV. The MAGIC observations covered the maximum of the SN brightening (on Jan 31, mag=10.5 AAVSO data: PSN J09554214+6940260). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC and VERITAS telescopes have observed relatively long-duration flaring activity from the blazar 1ES 1011+496 at z = 0.212 (RA=10h 15m 04.1s, Dec=+49d 26m 01s). The brightest very high energy (VHE ; >100 GeV) gamma-ray flux previously recorded from this blazar is approximately 7% of the flux (>200 GeV) observed from the Crab Nebula (J. Albert et al. 2007, ApJ 667, L21). Recent VERITAS and MAGIC observations exceed roughly 10 times this flux. VERITAS observations were taken almost every night between February 3, 2014 UTC (MJD 56691) and February 11, 2014 (MJD 56699). The preliminary analysis of all good-weather data yields a strong signal of about 3300 gamma rays in 13 hours of exposure, corresponding to a statistical significance of 43 standard deviations. The observed nightly integral flux above 200 GeV ranges between 25% and 75% of the flux measured by MAGIC from the Crab Nebula. Following a VERITAS alert to ground-based VHE observatories, the MAGIC telescopes observed the source nightly from February 6, 2014 UTC (MJD 56694) through February 11, 2014 (MJD 56699). The preliminary analysis of these data results in integral fluxes above 200 GeV (nightly averaged) ranging between of 45% and 75% of the flux from the Crab Nebula. Follow-up observations were also taken with Swift XRT / UVOT and at optical wavelengths. The 0.3-10 keV X-ray flux of 1ES1011+496 is also at the highest level ever seen by Swift (http://www.swift.psu.edu/monitoring/). The latest MAGIC and VERITAS observations performed on the night of February 11, 2014 show the high VHE flux persists. The MAGIC and VERITAS telescopes are entering the full Moon period, however the observations will be resumed on February 20, 2014 (UTC), if the weather conditions permit. Additional multiwavelength observations are encouraged. MAGIC is a system of two 17m-diameter imaging atmospheric Cherenkov telescopes (IACTs) located at the Canary island of La Palma, Spain. VERITAS is an array of four 12-m diameter IACTs located near Tucson, Arizona, USA. VERITAS and MAGIC are sensitive to astronomical sources of gamma-rays with energies ranging from approximately 50 GeV to greater than 50 TeV.

The MAGIC collaboration reports the discovery of very high energy (VHE ; E>100 GeV) gamma-ray emission from S3 0218+357 (RA=02h21m05.5s, DEC=+35d56m14s, J2000.0). The object was observed with the MAGIC telescopes for a total of 3.5 hours from 2014/07/23 to 2014/07/26. The preliminary analysis of these data resulted in the detection of S3 0218+357 with a statistical significance of more than 5 standard deviations. From the preliminary analysis, we estimate the VHE flux of this detection to be about 15% of the flux from the Crab Nebula in the energy range 100-200 GeV. S3 0218+357 is a gravitationally lensed blazar located at the redshift of 0.944+/-0.002 (Cohen et al., 2003, ApJ, 583, 67). Fermi-LAT observations during the flaring state of S3 0218+357 in 2012 revealed a series of flares with their counterparts after 11.46+/-0.16 days delay, interpreted as due to the gravitational lensing effect (Cheung et al. 2014, ApJ, 782, L14). On 2014 July 13 and 14 Fermi-LAT detected another flaring episode (ATel #6316). Due to the full-moon time, the MAGIC telescopes were not operational and could not observe S3 0218+357 after the original alert. However, observations scheduled at the expected time of arrival of the gravitationally lensed component led to the first significant detection of a gravitationally lensed blazar and the most distant source detected at VHE with Cherenkov telescopes to date. MAGIC observations on S3 0218+357 will continue during the next days and multiwavelength observations are encouraged. The MAGIC contact persons for these observations are R. Mirzoyan (Razmik.Mirzoyan@mpp.mpg.de) and J. Sitarek (jsitarek@ifae.es). MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located at the Canary island of La Palma, Spain, and designed to perform gamma-ray astrophysics in the energy range from 50 GeV to greater than 50 TeV.

The MAGIC collaboration reports the discovery of very high energy (VHE ; E>100 GeV) gamma-ray emission from MS1221.8+2452 (12h24m24.2s +24d36m24s, J2000.0). MS1221.8+2452 is a blazar located at a redshift of 0.218 (Sbarufatti et al., 2005, ApJ 635, 173) and classified as a high synchrotron peaked (HSP) BL Lac. It is one of the very few BL Lacs that has been imaged with the Hubble Space Telescope (Jannuzzi et al., 1997, ApJ 491, 146). It has been included in the ROSAT Bright Source Catalog (Voges et al., 1999, A&A 349, 389) and identified as XBL (X-Ray-Selected BL Lac) by the Einstein Extended Medium Sensitivity Survey (Rector et al. 2000, AJ 120, 1626). The object was observed with the MAGIC telescopes for 4 hours from 2013/04/30 to 2013/05/01. The preliminary analysis of these data resulted in the detection of MS1221.8+2452 with a statistical significance of more than 5 standard deviations. The VHE flux of this detection was estimated to be about 4% of the Crab nebula flux above 200 GeV. MS1221.8+2452 was observed with Swift during March and April 2013, showing flux variability ranging from 3e-12 erg/cm2/s to 13e-12 erg/cm2/s in the 0.3-10 keV energy range. This source was flagged as a promising VHE source candidate by the Fermi-LAT collaboration, information that was shared with the MAGIC collaboration (as well as other ground-based gamma-ray instruments). MAGIC observations on MS1221.8+2452 will continue during the next days until 2013/05/12 and multiwavelength observations are encouraged.

H1722+119 is a BL Lac object, that was listed as candidate TeV blazar in Costamante & Ghisellini (2002) based on its X-ray and radio properties. Its redshift is uncertain ; Sbarufatti et al. 2006 give z>0.17. The source has been detected by Fermi-LAT, in the Second Fermi Catalog with F(>1 GeV) (3.7+-0.3)e-09 cm^-2 s^-1 and with spectral index 1.92+-0.06. H1722+119 was observed for five nights by the MAGIC telescopes starting May 17th 2013 and collecting 11 hours of good quality data. A preliminary analysis yields a detection of the source with a statistical significance of more than 5 standard deviations. The VHE flux of this detection is about 2% of the flux from the Crab nebula above 140 GeV. The previous VHE gamma-ray observations of the source produced an upper limit of 4.2% Crab nebula flux above 140 GeV (Aleksic et al. 2011). The MAGIC observations were triggered by the extended optical high state of the source, reported by the Tuorla blazar monitoring program (http://users.utu.fi/kani/1m). At the beginning of May 2013 the source reached an R-band magnitude of 14.65, the brightest ever observed since 2005, when the monitoring started. We also analyzed the Fermi-LAT data, finding indication of a spectral index harder than reported in the Second Fermi Catalog. A Swift-XRT ToO observation was performed on 20th May. MAGIC will continue the observations of the source as soon as the moon conditions allow it again and multiwavelength observations are encouraged.

The MAGIC and VERITAS telescopes have observed an unprecedented flaring activity in the Very High Energy (VHE ; >100 GeV) gamma-ray flux from Markarian 421 (RA= 11 04 27.31, Dec=38 12 31.8, J2000.0). These observations were initially performed within a pre-planned extensive multi-instrument campaign that started in December 2012, and intensified in the last days because of the extreme VHE activity observed. Mrk421 is a high-synchrotron-peaked BL Lac located at redshift 0.031, which was first reported as a VHE emitter in 1992 (Punch et al 1992, Nature 358, 477). The typical VHE flux of this source is about 0.5 times the flux from the Crab Nebula (Crab Units, c.u.), as reported in Abdo et al 2011, ApJ 736, 131 and references therein, and the highest level of VHE activity ever measured for this source was about 10 c.u. (Gaidos et al. 1996, Nature 383, 319, and also Fortson et al. 2012, American Institute of Physics Conference Series, 1505, 514). The preliminary analysis of the VHE data taken with MAGIC and VERITAS during the last three consecutive nights (from 2013/04/11 to 2013/04/13) indicate a persistently high flux of about 5 c.u. above 300 GeV, but very variable and with maxima reaching beyond 11 c.u. This implies an increase by a factor of more than 20 with respect to the typical (not lowest) VHE flux from this source above 300 GeV, and represent the highest VHE activity recorded for this object to date. Besides MAGIC and VERITAS, the campaign also includes dedicated observations at radio and optical wavelengths with various instruments, and X-rays with Swift and NuSTAR. The source has been found to be also very high at optical and X-ray (see ATel #4974).

Following the communication from the Fermi-LAT collaboration on February 1st that PKS 1510-089 (z=0.36, R.A.= 15h 12m 50.5s, Dec.=-09d 05m 59.8s, J2000) underwent spectral hardening in MeV-GeV range (Dave Thompson, priv. comm. to TeV facilities) and ATel #3907 announcing enhanced gamma-ray emission observed by AGILE on February 2nd, the source was observed by MAGIC starting on February 3rd, just before the full moon shut down. The observations were resumed on February 19th and in total ~10 hours of data have been collected. The preliminary analysis of the data reveals a clear signal with a statistical significance of >5 sigma. The source had been previously detected to emit VHE gamma-rays by the H.E.S.S. telescope array in 2009 (Wagner, S., & Behera, B. 2010, 10th HEAD Meeting). Simultaneous to the MAGIC observations we have obtained optical R-band photometry and polarimetry with the KVA and Liverpool Telescopes. The source has undergone a minor optical outburst with a maximum brightness of R=15.3 (~2.3 mJy) measured on February 25th compared to a maximum brightness of R=13.1 (18 mJy) during the major outburst in 2009. The optical polarization has remained between 3% and 9% which is within the typical range for this quasar.

The source PG 1553+113 is a well-known TeV emitter, likely located at redshift 0.4-0.5 (Danforth et al. 2010). Its state has been monitored by MAGIC since February 2005. In March 2012, a high emission state at VHE, X-ray, optical, and infrared wavelengths was reported (ATel #3977). During the night of April 19-20th (MJD 56037), the source was observed by MAGIC for a total of 1.1 hour of good quality data. A strong signal corresponding to a statistical significance above 15 standard deviations in the VHE range was detected. The level obtained with the preliminary analysis reaches the Crab Nebula flux level at ~100 GeV. It is the highest state of PG 1553+113 ever detected at these energies. The mean flux at 100 GeV measured by MAGIC between 2005 and 2009 was ~50% of the Crab Nebula flux (J. Aleksic et al., 2012). Follow up observations carried out in the following nights confirm that the source persists in this high state. Simultaneous optical observations performed in the R band by the KVA telescope also show increased emission. The maximum flux reached is 13.14 ± 0.01 mJy (MJD 56040). The source is brighter than during the high state reported one month ago (12.2 ± 0.2 mJy ; http://users.utu.fi/kani/1m/PG_1553+113_jy.html ). Optical polarimetric observations were taken with the Liverpool telescope as part of a joint observational program with MAGIC. Preliminary photometric observations in the J, H and K bands with the REM telescope show an increasing activity of the source during the last week. In addition, automatic analysis procedures applied to Swift/XRT data collected on April 17th and 21st indicate that the source is also brightening in X rays. The preliminary Swift/XRT lightcurve is publicly available at: http://www.swift.psu.edu/monitoring/data/PG1553+113/lightcurve.png. Dedicated analyses are in progress. Given the high activity detected, we strongly encourage multi-wavelength observations of the source.

The MAGIC telescopes have observed a high VHE (E>~100 GeV) gamma-ray flux from the galaxy IC 310. The object (RA: 03h 16m 43.0s, Dec: +41d 19m 29s, J2000) is a TeV radio-loud galaxy located in the Perseus Cluster of galaxies at redshift 0.0189 (Falco et al. 1999). Although formerly considered to be an archetypical head-tail galaxy, recent radio-interferometric observations have shown that IC 310 hosts a blazar-type central engine (Kadler et al. 2012, A&A, 538, L1). The source was discovered as a VHE emitter by MAGIC in the 2009-2010 campaign, showing a mean flux level of (2.5 +- 0.4)% of the Crab Nebula flux above 300 GeV (J. Aleksic et al. (MAGIC Coll.), Astrophys. J. 723(2010) L207). MAGIC observations were carried out on November 12, 2012 (MJD 56243.9 - 56244.1) right after the upgrade of the MAGIC telescopes has been completed. Preliminary analysis resulted in a detection with the significance of 25 standard deviations. The mean flux above 300 GeV is higher than 50% of the Crab Nebula flux which is the highest ever detected from IC 310 in the VHE range. MAGIC will continue to observe the source and multi-frequency observations are strongly encouraged.

The MAGIC telescopes have observed an increased VHE (E>~100 GeV) gamma-ray flux from the blazar PG 1553+113 in the course of a multi-wavelength campaign started on 2012 February 23. PG 1553+113 (RA: 15h 55m 43.0s Dec: +11d 11m 24s) is a TeV BL-Lac object likely located at redshift 0.4-0.5 (Danforth et al. 2010). Between February 23 and March 5 an extensive multi-wavelength campaign coordinated by the MAGIC Collaboration was performed, involving besides MAGIC, radio (Metsahovi), near-infrared (REM), optical (KVA), UV (Swift/UVOT), and X-ray (Swift/XRT) observations. Preliminary analysis of MAGIC data shows a firm detection with significance around 15 sigma in 4 hours of good quality data. According to this analysis the estimated flux is above 15% Crab in the VHE range, one of the highest fluxes ever detected from PG 1553+113. The analysis of MAGIC data is still in progress. Preliminary analysis of X-ray data taken with Swift/XRT reports a 2-10 keV flux rising from (16.8+/-1.0)E-12 erg/cm2/s to (23.0+/-1.3)E-12 erg/cm2/s between February 16 to March 2. The XRT spectrum obtained on single daily snapshots is fairly fitted with an absorbed power law with an absorbing column density fixed to the Galactic value of 3.65E20 cm-2 (Kalberla et al. 2005), yielding a photon index around 2.3+/-0.1, relatively stable within errors. Swift/UVOT observed with all the optical and UV filters, providing the following preliminary averaged magnitudes, not corrected for absorption, and fluxes, corrected for Galactic extinctions due to reddening of E(B-V)=0.052 mag in the direction of the source (Schlegel et al 1998).

The MAGIC Collaboration reports the discovery of Very High Energy (VHE ; E>100 GeV) gamma-ray emission from the BL Lac object 1ES 1727+502 (also known as OT546) with redshift z=0.055. The source was selected from the compilation of Costamante, L. & Ghisellini, G. 2002, A&A, 384, 56. Previous observations with the single MAGIC-I telescope yielded an upper limit on the level of 11.8% of the Crab Nebula flux above 140 GeV (J. Aleksic et al. (MAGIC Coll.), Astrophys. J. 729 (2010) 115). A total observation time of 12.5 hours was collected between 2011 May 6th to June 10th in stereoscopic mode with the two 17 m diameter imaging Cherenkov telescopes on La Palma, Canary Islands, Spain. The preliminary analysis of this data using the standard analysis chain yields a detection of 76 gamma-rays above 150 GeV, corresponding to a statistical significance of 5 standard deviations. The observed flux is estimated to be (1.7+/-0.6)% of the Crab Nebula flux above 150 GeV, well below the previous upper limit. Errors are statistical only.

The unidentified and variable TeV gamma-ray source HESS J0632+057 was recently reported to show a strong flux increase in X-rays by Swift (ATel #3152) starting Jan. 23, 2011 and staying active at least up to Feb. 6, 2011. Shortly afterwards an increase in the TeV flux around Feb. 7/8, 2011 was reported by the VERITAS collaboration (Atel #3153). The TeV source HESS J0632+057 was suggested to be a binary system and the recent X-ray measurements suggest an orbital period of ~ 320 days (ATel #3152). MAGIC monitored HESS J0632+057 during the same time period as Swift and VERITAS. We observed the source between Feb. 7-9, 2011 and our preliminary analysis results in a detection of a significant (above 5 standard deviations) gamma-ray signal above 200 GeV. The estimated flux corresponds to about 3.4% of the Crab Nebula flux in the same energy band. No indication of day-to-day variability is found. Further observations of HESS J0632+057 with MAGIC are planned for the next nights, to monitor the flux level and duration of the gamma-ray activity. MAGIC consists of two 17m diameter imaging air Cherenkov telescopes operating in stereoscopic mode located on La Palma, Canary Islands, Spain. Questions regarding the MAGIC observations should be directed to Mose Mariotti (mose.mariotti@pd.infn.it).

The MAGIC Collaboration reports an outburst of the Very High Energy (VHE ; >100 GeV) gamma-ray blazar 1ES0806+524. This high frequency peaked BL Lacertae object (with redshift of 0.138) was first discovered by VERITAS using 65 hours of data collected between November 2006 and April 2008 (Acciari et al. 2009, ApJL, 690, 126). No variability was found during the VERITAS observations. The MAGIC observations were triggered by an optical high-state of the source, reported by the Tuorla blazar monitoring program http://users.utu.fi/kani/1m/1ES_0806+524.html. The VHE detection is based on a 3.3 hour-long observation performed on 2011 February 24th in stereoscopic mode with the two 17m diameter imaging Cherenkov telescopes on La Palma, Canary Islands, Spain. The preliminary analysis of the MAGIC data using standard cuts yields a detection of 44 gamma-rays above 250 GeV, corresponding to a pre-trial statistical significance of 6.7 standard deviations. The observed flux is estimated to be ~5.4% of the Crab nebula flux above 250 GeV, three times higher than the previous VERITAS detection (1.8% of the Crab nebula flux). Observations on the 23rd of February did not result in a detection of the source, indicating variability on the time scale of about one day. MAGIC will continue observations of 1ES0806+524. Observations at other wavelengths are encouraged. Questions regarding the MAGIC observations should be directed to Mose Mariotti (mose.mariotti@pi.infn.it).

After re-analysis of archival data, the MAGIC Collaboration reports the discovery of very high energy (VHE ; E >100 GeV) gamma-ray emission from the BL Lac object 1ES0033+595 (RA: 00:35:52.63, Dec.: 59:50:04.56), of unknown redshift. The source was observed with the MAGIC stereoscopic system for about 24 hours in August through October 2009 during the commissioning phase of the instrument. Preliminary analysis using the standard analysis chain shows an excess of 357 photons above 100 GeV, that corresponds to a statistical significance of 5.2 sigmas after trials. The observed flux is estimated to be 1.5% of the Crab nebula flux above 150 GeV, and it rapidly decreases with energy. No hint of variability is seen in the preliminary VHE light curve. This blazar is currently observable from the Northern hemisphere.

The MAGIC Collaboration reports the discovery of Very High Energy (VHE ; >100 GeV) gamma-ray emission from the BL Lac object 1ES 1215+303 (also known as ON325) with z=0.130 (White et al. 2000 give z=0.237) based on a 5.6 hour-long observation performed from 2011 January 2nd to 5th in stereoscopic mode with the two 17m diameter imaging Cherenkov telescopes on La Palma, Canary Islands, Spain. The preliminary analysis of the MAGIC data using standard cuts yields a detection of 25 gamma-rays above 250 GeV, corresponding to a statistical significance of 5 standard deviations. The observed flux is estimated to be (2.0+/-1.0)% of the Crab nebula flux above 250 GeV. The source has been flagged as a promising VHE source candidate by the Fermi-LAT collaboration in October 2010. The MAGIC observations were triggered by an optical high-state of the source, reported by the Tuorla blazar monitoring program (http://users.utu.fi/kani/1m/ON_325.html). Target of Opportunity Observations with Swift have also been performed. Fast analysis of the data show that in X-rays the flux is almost doubled respect to previous observation (December 2009) but the spectral shape is almost unchanged. We thank the Swift team for accepting and promptly scheduling the X-ray observations. MAGIC observations suggest also a higher state of a known VHE gamma-ray emitter 1ES 1218+304 in the same field of view, from which an excess of above 5 standard deviation was observed. MAGIC will continue observations of both sources. Observations at other wavelengths are encouraged. Questions regarding the MAGIC observations should be directed to Mose Mariotti (mose.mariotti@pd.infn.it).

The MAGIC collaboration reports the detection of a very high gamma ray flare from the Flat Spectrum Radio Quasar 4C +21.35 (PKS 1222+21, z=0.432, RA: 12h24m54.4s DEC: +21d22m46s, J2000) at energies above 100 GeV. The observation was performed in stereoscopic mode during low intensity moon light using the two 17m diameter imaging Cherenkov telescopes on La Palma, Canary Islands, Spain, during 0.5 hours on MJD 55364 (June 17th 2010). The preliminary results indicate a significant gamma-ray signal of ~120 excess events corresponding to >8 sigma level above the background. The integral flux for gamma-rays with energies above 100 GeV is estimated to be at >=30% of the Crab nebula flux. 4C +21.35 has been recently found to be a very high energy (VHE) gamma-ray emitter in the 100-300 GeV band by analyzing public Fermi/LAT data (Neronov et al. ATel #2617), and at the end of April 2010 a bright flare in the energy band above 100 MeV was reported by Fermi/LAT and AGILE (ATel #2584, #2641) along with a flare in near infrared (MJD 55275, ATel #2626).This is the ground-based detection of this source at VHE by a Cherenkov instrument. MAGIC will continue to observe 4C+21.35 and multi-frequency observations are strongly encouraged.

The MAGIC Collaboration reports the detection of Very High Energy (VHE) gamma-ray emission from a position consistent with NGC 1275, the central radio galaxy of the Perseus cluster of galaxies. The MAGIC observations were carried out in stereoscopic mode starting from August 2010, accumulating 14 h of good quality data. Preliminary analysis using the standard analysis chain with a energy threshold of 100 GeV, shows an excess of 280 gamma-rays, corresponding to a statistical significance of 5.2 standard deviations. The observed flux is estimated to be ~3% of the Crab nebula flux above 100 GeV, and it decreases rapidly with energy. No signal is detected above 400 GeV. The MAGIC VHE detection happened during a period of increased high gamma-ray activity of NGC 1275, as reported in July 2010 by the Fermi/LAT collaboration, ATel#2737, and continuing until October, according to an analysis of public Fermi/LAT data. MAGIC will continue observations of NGC1275. Observations at other wavelengths are encouraged.

The MAGIC Collaboration reports the discovery of Very High Energy (VHE ; >100 GeV) gamma-ray emission from the High Frequency peaking BL Lac object B3 2247+381 with z=0.1187. The source is positionally consistent with the Fermi-LAT gamma-ray source 1FGL J2250.1+3825 (RA 22 50 06.6 dec +38 25 58, J2000), which was flagged as a promising VHE source candidate by the Fermi-LAT collaboration, information which was shared with the MAGIC collaboration (as well as other IACTs) back in October 2009. The MAGIC observations were triggered by an optical high-state of the source, reported by the Tuorla blazar monitoring program (http://users.utu.fi/kani/1m/B3_2247+381.html). The VHE detection is based on a 9.3 hour-long observation performed on 2010 September 30th, October 1st, 2nd, 4th, 5th and 6th in stereoscopic mode with the two 17m diameter imaging Cherenkov telescopes on La Palma, Canary Islands, Spain. The preliminary analysis of the MAGIC data using standard cuts yields a detection of 64 gamma-rays above 150 GeV, corresponding to a pre-trial statistical significance of 5 standard deviations. The observed flux is estimated to be ~2% of the Crab nebula flux above 150 GeV. Target of Opportunity Observations with Swift have also been performed on this source location. A preliminary analysis of the Swift/XRT data shows that the X-ray flux from the source is ~4 times higher than during last observation (spring 2010). Further Swift observations are expected until October 15. We thank the Swift team for accepting and promptly scheduling the X-ray observations. MAGIC will continue observations of B3 2247+381. Observations at other wavelengths are encouraged.

The MAGIC telescopes observed the Crab Nebula in stereoscopic mode during the period of enhanced activity reported by AGILE (ATel #2855) and Fermi-LAT (ATel #2861) in September 2010. The observations started at MJD 55459.2070 (September 20th) lasting for 58 minutes. The average flux and spectrum during these observations were compared to a reference Crab Nebula data sample taken between 2009 October to 2010 January. No significant change was detected in flux or spectral shape: the ratio of the differential flux at 1 TeV in the flare sample and the reference sample is dN/dE(1TeV)_flare/dN/dE(1TeV)_ref=1.06+/-0.15_stat+/-0.15_syst ; the difference between the photon indices, fitting data with energies between 1 and 10 TeV, is Alpha_ref - Alpha_flare=0.06+/-0.14_stat+/-0.15_syst. Within statistical errors, these findings do not support the evidence of an increase in the flux of the Crab Nebula at very high energies by a factor 3 to 4 as reported by ARGO-YBJ (ATel #2921), if this increase was steady. MAGIC consists of two 17m diameter imaging air Cherenkov telescopes located on La Palma, Canary Islands, Spain. Questions regarding the MAGIC observations should be directed to Mose Mariotti (mose.mariotti@pd.infn.it).