J. Jesús González

First Light with RATIR: An Automated 6-band Optical/NIR Imaging Camera

The Reionization and Transients InfraRed camera (RATIR) is a simultaneous optical/NIR multi-band imaging camera which is 100% time-dedicated to the followup of Gamma-ray Bursts. The camera is mounted on the 1.5-meter Johnson telescope of the Mexican Observatorio Astronomico Nacional on Sierra San Pedro Martir in Baja California. With rapid slew capability and autonomous interrupt capabilities, the system will image GRBs in 6 bands (i, r, Z, Y, J, and H) within minutes of receiving a satellite position, detecting optically faint afterglows in the NIR and quickly alerting the community to potential GRBs at high redshift (z>6-10). We report here on this Springs first light observing campaign with RATIR. We summarize the instrumental characteristics, capabilities, and observing modes.

IPTF14yb: The first discovery of a gamma-ray burst afterglow independent of a high-energy trigger

We report here the discovery by the Intermediate Palomar Transient Factory (iPTF) of iPTF14yb, a luminous (M_r ≈ 27.8 mag), cosmological (redshift 1.9733), rapidly fading optical transient. We demonstrate, based on probabilistic arguments and a comparison with the broader population, that iPTF14yb is the optical afterglow of the long-duration gamma-ray burst GRB 140226A. This marks the first unambiguous discovery of a GRB afterglow prior to (and thus entirely independent of) an associated high-energy trigger. We estimate the rate of iPTF14yb-like sources (i.e., cosmologically distant relativistic explosions) based on iPTF observations, inferring an all-sky value of yr^−1 (68% confidence interval of 110–2000 yr−1). Our derived rate is consistent (within the large uncertainty) with the all-sky rate of on-axis GRBs derived by the Swift satellite. Finally, we briefly discuss the implications of the nondetection to date of bona fide orphan afterglows (i.e., those lacking detectable high-energy emission) on GRB beaming and the degree of baryon loading in these relativistic jets.

Mechanical configurations for the reionization and transients infrared camera (RATIR)

RATIR (The Reionization and Transients Infrared Camera/Telescope) is an optical infrared camera in the 1.5 m telescope in the Mexican National Astronomical Observatory, OAN, in San Pedro Martir, Baja California. The primary goal of RATIR is to remotely observe Gamma Ray Bursts as detected by the SWIFT satellite. This document describes the problem definition, the mechanical calculations, the conceptual design, the finite element analysis, the different configurations proposed and the mechanical performance of the main Support Structure and Dichroic Mounts for RATIR.

OSIRIS tunable imager and spectrograph for the GTC: from design to commissioning

OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy) was the optical Day One instrument for the 10.4m Spanish telescope GTC. It is installed at the Observatorio del Roque de Los Muchachos (La Palma, Spain). This instrument has been operational since March-2009 and covers from 360 to 1000 nm. OSIRIS observing modes include direct imaging with tunable and conventional filters, long slit and low resolution spectroscopy. OSIRIS wide field of view and high efficiency provide a powerful tool for the scientific exploitation of GTC. OSIRIS was developed by a Consortium formed by the Instituto de Astrofísica de Canarias (IAC) and the Instituto de Astronomía de la Universidad Nacional Autónoma de México (IA-UNAM). The latter was in charge of the optical design, the manufacture of the camera and collaboration in the assembly, integration and verification process. The IAC was responsible for the remaining design of the instrument and it was the project leader. The present paper considers the development of the instrument from its design to its present situation in which is in used by the scientific community.

OSIRIS optical design

The Optical System for Imaging and low Resolution Integrated Spectroscopy (OSIRIS) is a first generation instrument for the 10.4-m Gran Telescopio Canarias (GTC) that will be operational in mid-2004. On such a large telescope, OSIRIS is the first instrument to use tunable filters, combined with charge shuffling capabilities, covering the wavelength range (365 - 1000 nm). To be installed first at a Nasmyth platform, OSIRIS is also compact enough to fit in the Cassegrain focus envelope. This paper discusses the OSIRIS optical design process based on the classical collimator plus camera focal reducer configuration concept. To provide a wide mode and resolution versatility, several combinations of grisms, color, order sorter, interference and tunable filters are attainable in the collimated beam, near the pupil. The OSIRIS geometry, specifications, features, and performance are briefly discussed. Subsection (#5) is centered on the pupil size to calculate angular magnification and collimator FOV. These values are compared with those taken from similar instruments for 6.5-m to 10-m telescopes. This contribution is meant to share our experience on the optical design issue with colleagues not necessarily familiarized with astronomical instrumentation design. A previous approach on the OSIRIS optical design and two more general descriptions are available.

TSPM f/5 Nasmyth configuration

We present the optical design, the error budget, the differential distortion budget and the baffle design of the Telescopio San Pedro Mártir f/5 Nasmyth configuration. The TSPM in its Cassegrain configuration will be assembled around a closed design (converted MMT/Magellan telescope) with most of its optical parts already manufactured. To anticipate for future possible upgrades, the project includes the design of an extreme f/5 Nasmyth configuration. Our optical design demonstrates the feasibility of the configuration, closes the interfaces to the telescope, provides a full picture of the expected performance, and identifies the critical points involved in the configuration.

Preliminary design for the f/5 Nasmyth tertiary mirror configuration for the TSPM

The preliminary design for the f/5 Nasmyth tertiary mirror opto-mechanical configuration for the 6.5m Telescopio San Pedro Mártir (TSPM), to be installed at the Observatorio Astronómico Nacional (OAN) in the Sierra San Pedro Mártir in Baja California is presented. The proposed system consists of support and alignment of the honeycomb mirror within the cell, the correction of the optical surface deformation, both tasks by means of an active push-pull pneumatic system and the correction of the displacements and rotations transferred by the Tube support structure to the configuration by means of electro-mechanical actuators. This optical configuration and four folded Cassegrain stations will be fully defined after first light of the f/5 Cassegrain configuration, so the requirements and considerations of these positions also need to be taken into account.

Mechanical preliminary design of the 6.5 meter Telescopio San Pedro Mártir (TSPM)

The Telescopio San Pedro Mártir project intends to build a 6.5 meters telescope with alt-azimuth mount and it has currently finished the preliminary design. The project is an association between Instituto de Astronomía de la Universidad Nacional Autónoma de México and the Instituto Nacional de Astrofísica, Óptica Electrónica in partnership with the University of Arizona and the Smithsonian Astrophysical Observatory. The telescope preliminary design this is lead and developed at Querétaro by the Centro de Ingeniería y Desarrollo Industrial. An overview of the preliminary design and the structural design updates are summarized in this paper.

The Telescopio San Pedro Mártir project

The Telescopio San Pedro Martir project intends to construct a 6.5m telescope to be installed at the Observatorio Astron´omico Nacional in the Sierra San Pedro M´artir in northern Baja California, Mexico. The project is an association of Mexican institutions, lead by the Instituto Nacional de Astrofısica, Optica y Electronica and UNAM’s Instituto de Astronomia, in partnership with the Smithsonian Astrophysical Observatory and the University of Arizona’s Department of Astronomy and Steward Observatory. The project is advancing through the design stage, having completed five design reviews of different subsystems in 2016 and 2017 (enclosure and services: PDR, CDR; optical design: PDR; optics: progress review; telescope: PDR). Once completed, the partners plan to operate the MMT and TSPM as a binational astrophysical observatory.

Recent developments at the OAN-SPM

The Observatorio Astron´omico Nacional on the Sierra San Pedro M´artir (OAN-SPM) in Baja California, Mexico is currently undergoing a substantial expansion in its observational infrastructure. The OAN-SPM’s three principal telescopes were installed in the 1970s. In 2015, the BOOTES-5 telescope was installed and is now operational (partners: Mexico, Spain, South Korea). In 2011 the construction of the TAOS-II project begun and its three telescopes are now in commissioning (partners: Taiwan, Mexico, USA, Canada). Also undergoing commissioning are the COATLI and DDOTI projects (both: Mexico, USA). Two projects, COLIBR´I and SAINT-EX are about to begin construction (COLIBR´I: Mexico, France; SAINT-EX: Switzerland, Mexico, UK). Finally, the Telescopio San Pedro M´artir project is advancing through its design phase (partners: Mexico, USA). All save the TSPM are fully funded, so the OAN-SPM will host 11-12 telescopes by the 2020’s, ranging in size from 28cm to 6.5m.