Abel Bernal

Destruction of the Environment of the BN-KL Nebula

Resumen en: We present the velocity structure of the 2.12 micron H2 emission in Orion, obtained with an IR Fabry-Perot interferometer with a spectral resolution of 2...

The isolated interacting galaxy pair NGC 5426/27 (Arp 271)

We present H alpha observations of the isolated interacting galaxy pair NGC 5426/27 using the scanning Fabry-Perot interferometer PUMA. The velocity field, various kinematical parameters and rotation curve for each galaxy were derived. The FWHM map and the residual velocities map were also computed to study the role of non-circular motions of the gas. Most of these motions can be associated with the presence of spiral arms and structure such as central bars. We found a small bar-like structure in NGC 5426, a distorted velocity field for NGC 5427 and a bridge-like feature between both galaxies which seems to be associated with NGC 5426. Using the observed rotation curves, a range of possible masses was computed for each galaxy. These were compared with the orbital mass of the pair derived from the relative motion of the participants. The rotation curve of each galaxy was also used to fit different mass distribution models considering the most common theoretical dark halo models. An analysis of the interaction process is presented and a possible 3D scenario for this encounter is also suggested.

Search for TeV Gamma-Ray Emission from Point-like Sources in the Inner Galactic Plane with a Partial Configuration of the HAWC Observatory

Author(s): Abeysekara, AU; Alfaro, R; Alvarez, C; Alvarez, JD; Arceo, R; Arteaga-Vela Zquez, JC; Solares, HAA; Barber, AS; Baughman, BM; Bautista-Elivar, N; Reyes, ADB; Belmont, E; Benzvi, SY; Bernal, A; Braun, J; Caballero-Mora, KS; Capistran, T; Carraminana, A; Casanova, S; Castillo, M; Cotti, U; Cotzomi, J; Leon, SCD; Fuente, EDL; Leon, CD; Deyoung, T; Diaz Hernandez, R; Dingus, BL; Duvernois, MA; Ellsworth, RW; Enriquez-Rivera, O; Fiorino, DW; Fraija, N; Garfias, F; Gonzalez, MM; Goodman, JA; Gussert, M; Hampel-Arias, Z; Harding, JP; Hernandez, S; Huntemeyer, P; Hui, CM; Imran, A; Iriarte, A; Karn, P; Kieda, D; Lara, A; Lauer, RJ; Lee, WH; Lennarz, D; Vargas, HL; Linnemann, JT; Longo, M; Raya, GL; Malone, K; Marinelli, A; Marinelli, SS; Martinez, H; Martinez, O; Martinez-Castro, J; Matthews, JA; Miranda-Romagnoli, P; Moreno, E; Mostafa, M; Nellen, L; Newbold, M; Noriega-Papaqui, R; Patricelli, B; Pelayo, R; Perez-Perez, EG; Pretz, J; Ren, Z; Riviere, C; Rosa-Gonzalez, D; Salazar, H; Greus, FS; Sandoval, A; Schneider, M; Sinnis, G; Smith, AJ; Woodle, KS; Springer, RW; Taboada, I; Tibolla, O; Tollefson, K | Abstract:

CAMILA: Infrared Camera/Spectrograph for OAN-SPM

The development of the IR camera and spectrograph (CAMILA) is described. It is based on a NICMOS 3 HgCdTe detector developed by Rockwell with a spectral response of 1 to 2.5 micrometers . The initial configuration of the system was recently concluded and consists of the following components: detector cryostat, detector control electronics, low noise preamplifiers, detector-PC interface, operating system and optics. The characterization of the electronics and the science grade chip are presented. The complete optical configuration allows the following modes of operation: direct imaging (12 filter positions), polarimetry and spectroscopy on three dispersion modes (low, medium, and high resolution). Preliminary spectroscopic results at the H band with R equals 1500 are presented. The project is a collaborative effort of groups from IAUNAM and UMASS (Amherst) and will be used mainly at the 2.1-m telescope of San Pedro Martir, B.C. (Mexico).

UNAM scanning Fabry-Perot interferometer (PUMA) for the study of interstellar medium

The system called PUMA is an instrument consisting of a focal reducer coupled to a scanning Fabry-Perot interferometer (SFPI), which is being developed for the Observatorio Astronomicao Nacional at San Pedro Martir, B.C. It will be installed at the 2.0 m Ritchey-Chretien telescope with a focal ratio of F/7.9. It has interference filters, a calibration system, and field diaphragms. The SFPI can be moved out of the optical path in order to acquire direct images. The images produced by this instrument will be focused on an optoelectronic detector, a CCD, or a Mepsicron, depending on the spectral range used.

PUMILA: A Near-infrared Spectrograph for the Kinematic Study of the Interstellar Medium.

We are developing an instrument to study the morphology and kinematics of the molecular gas and its interrelationship with the ionized gas in star forming regions, planetary nebulae and supernova remnants in our Galaxy and other galaxies, as well as the kinematics of the IR emitting gas in starburst and interacting galaxies. This instrument consists of a water-free fused silica scanning Fabry-Perot interferometer optimized in the spectral range from 1.5 to 2.4 micrometers with high spectral resolution. It will be installed in the collimated beam of a nearly 2:1 focal reducer, designed for the Cassegrain focus of the 2.1 m telescope of the San Pedro Martir National Astronomical Observatory. Mexico, in its f/7.5 configuration, yielding a field of view of 11.6 arc-min. It will provide direct images as well as interferograms to be focused on a 1024 X 1024 HAWAII array, covering a spectral range from 0.9 to 2.5 micrometers .

PUMA: the first results of a nebular spectrograph for the study of the kinematics of interstellar medium

The kinematics of the interstellar medium may be studied by means of a scanning Fabry-Perot interferometer (SFPI). This allows the coverage of a wider field of view with higher spatial and spectral resolution than when a high-dispersion classical spectrograph is used. The system called PUMA consists of a focal reducer and a SFPI installed in the 2.1 m telescope of the San Pedro Martir National Astronomical Observatory (SPM), Mexico, in its f/7.5 configuration. It covers a field of view of 10 arcmin providing direct images as well as interferograms which are focused on a 1024 X 1024 Tektronix CCD, covering a wide spectral range. It is considered the integration of other optical elements for further developments. The optomechanical system and the developed software allow exact, remote positioning of all movable parts and control the FPI scanning and data acquisition. The parallelism of the interferometer plates is automatically achieved by a custom method. The PUMA provides spectral resolutions of 0.414 Angstrom and a free spectral range of 19.8 Angstrom. Results of high quality that compete with those obtained by similar systems in bigger telescopes, are presented.

Monitoring at TeV Energies with M@TE

Blazars are extremely variable objects emitting radiation across the electromagnetic spectrum and showing variability on time scales from minutes to years. Simultaneous multi-wavelength observations are crucial for understanding the emission mechanisms. In particular the study of their TeV emission is relevant to test the dominant radiative process at such energies (e.g. leptonic models predict a correlation between X-ray and TeV emission). As well, the correlation with the bump at low energy or the possible common detection with a neutrino signal can be relevant to constrain the physical model. From radio via optical and from X-ray to gamma rays, a variety of instruments, as OVRO and Fermi, are already monitoring blazars. At TeV energies, long-term monitoring is currently carried out by HAWC and FACT. Towards 24/7 continuous observations, the goal is to have similar monitoring telescopes at locations around the globe in order to close temporal gaps and compile light curves with homogeneous sensitivity. With the M@TE (Monitoring at TeV energies) project, we are planning to install an Imaging Air Cherenkov Telescope equipped with an improved version of the FACT camera and the mechanical structure of one of the mounts of the HEGRA experiment at the site of San Pedro Martir in Mexico. Featuring excellent observation conditions, this location provides a variety of instruments from radio to optical wavelength allowing for coordinated multi-wavelength blazar studies. In this work, we will present the status of the project.

A water quality monitoring system for HAWC

HAWC (High Altitude Water Cherenkov), is a gamma ray (γ) large aperture observatory with high sensitivity that will be able to continuously monitor the sky for transient sources of photons with energies between 100 GeV and 100 TeV. HAWC is under construction in Sierra Negra, Puebla, Mexico, which is located at a high altitude of 4100m. HAWC will be an array of 300 Cherenkov detectors each one with 200,000 liters of highly pure water. The sensitivity of the instrument depends strongly on the water quality. We present the design and construction of the HAWC water quality monitoring system. We seek monitor the transparency in violet-blue range to achieve and maintain the required water transparency quality in each detector. The system is robust and user friendly. The measurements are reproducible. Also we present some results from the monitoring the water from the VAMOS detector tanks and of the filtering system.

Analog front end board electronics proposal for the HAWC Observatory

HAWC (High Altitude Water Cherenkov) is a high energy Gamma ray detector-telescope under construction at an altitude of 4100 m in the Sierra Negra volcano, Mexico. HAWC is a international Mexico/USA collaboration and it will consist of a array of 300 tanks filled water and three photomultipliers tubes near the bottom of each tank. This work discuss some analog electronics solutions and the use of high speed differential amplifiers for tracking the high frequency pulses from the photomultiplier tubes. It also looks towards the update of the present analog front end board electronics of the water detector tanks.