NAHUAL status: A CONCEPT FOR A HIGH RESOLUTION IR SPECTROGRAPH

FOR A 10-M SEGMENTED TELESCOPE (GTC)

Perryman 1992

Motivation: To extend the parameter space of planet searches(ages, masses, rotation). Very low-mass primaries (Martin et al. 2006, Blake et al. 2007, Zapatero Osorio et al. 2007, 2009)

T Tauri stars (Huélamo et al. 2008), Young MS stars, Red giants

Team• Eduardo Martín (PI)(CAB, UCF) • Eike Guenther (co-PI), Artie Hatzes, Sylvio Klose (TLS)• Carlos del Burgo (co-PI), Tully Peacoke (DIAS)• Antonio Amorim, André Moitinho, J. Lima (Lisboa)• Víctor S. Béjar, Enric Pallé, Florian Rodler, Luisa Valdivielso, Manuel Amate, Javier

Fuentes, Darío Sosa (IAC)• Pedro Esparza (U La Laguna), Carlos Alvarez (GTC) • Jose Antonio Caballero, David Montes (UCM)• Maria Rosa Zapatero Osorio, David Barrado (CAB)• Carlo Baffa, Sofía Randich (Arcetri)• Humberto Campins, Michele Montgomery, Rohit Deshpande, Ramarao Tata, Robert

Peale (U Central Florida)

Science cases• RV searches for habitable exoplanets in cool stars (late-M, L) • Follow-up of exoplanet candidates in the IR• Magnetic activity in cool stars and brown dwarfs• Rotation in cool stars and brown dwarfs• Astroseismology• Chemical abundances in stars and solar system objects• Very low-mass binaries• Very young binaries • BD companions of WDs (including CVs) • Stellar populations in the Milky Way and other galaxies • Black holes in AGNs • Gamma ray bursts

Community interest• 7 workshops held so far (La Gomera, Segovia, Jena, Cádiz, Miami, Fuerteventura,

Sintra)• About 80 different participants in those workshops• Seed for instrument proposed for Calar Alto 3.5-m (CARMENES) • Need for high-precision RV capabilities mentioned in Exoplanet Task Force and Blue

Dots reports.

• Funding collected since 2005: • 600 Keuros from MEC• 200 Keuros from Tautenburg• 100 Keuros from IAC • 40 Keuros from Lisbon

Observing mode discrepancy

NAHUAL team: Single object. High stability (no moving parts). R=60,000. Wav. Range=0.9—1.8 microns. FOV=3 arcsec.

GTC: Multi-object capability. R=20,000. Range=0.95—2.45 microns. FOV≈10 arcmin.

Location

GTC floating basement. Fiber-fed through folded Cass G. About 40 meters of fibers (98% transmission in Y,J,H, but only about 30% for K-band).

AO Nasmyth platform (stringent constraints on space and weight).

Coudé room (longer fibers).

Folded cass (supported by GTC).

GTC TELESCOPE

Nahual project web page

NAHUAL

http://www.iac.es/proyecto/nahual

Martín et al. 2005, AN

Optical design

FOCAL PLANE WHEEL.-ADC-IMAGE SLICER-SLIT APERTURES

Detector

Intermediate focal plane

Off axis parabola

ECHELLEGRATING

FOLDER MIRROR

CROSS DISPERSIONUNIT

CAMERA(Three Mirrors+ Corrector)

Off-axisparabola

CRYOSTAT ENTRANCE

CALIBRATIONGAS CELL

U. Laux, E. Sánchez Blanco,S. Gennari, T. Peacocke

Wide wavelength coverage

))sin()(sin()/( nd

1 1.5 2 2.5

20

25

30

35

40

45

50Wavelenght range coverage: Grating 31.6 lin/mm @ 71º

Central Wavelenght at blaze angle

J H K

2330mm

1200mm

Conceptual mechanical design

High stability cryostat

Collaboration between Arcetri, IAC and Lisbon

Sizes of optical elements

Element Clear aperture (mm)

FP1 ~ 2 x 2

OAP1 , OAP2 109

ECHELLE 109 x 220

FLD1 ~ 10 x 10

FP2 ~ 2 x 2

OAP3 109

CROSS DISP 109

DETECTOR (HAWAII-2) 36.8

Prisms of ZnSe

Ohara GmbH150.00 ±1.0 mm50.00 ±1.0 mm 40.000 euros

What calibration?

Gas cell development

Mid-resolution gas cell spectra

Collaboration with R. Peale (UCF)

17

Figure by R. Tata

NIR RVPlanet SearchSpace

18

NAHUAL SENSITIVITY

e = 0.3i = 30o

Primary dM5 Mass 0.2 Msol

3 m/s ((3 sigma) in 300 s for K=9 and D = 10 m.

1 E

art

h

10

Eart

hs

Summary

• NAHUAL could be working at GTC in 2013 as visitor instrument, or as mid and high-resolution near-infrared spectrograph common-user @ GTC in 2016. Status TBD until mid-2010 ….

• 5 years of experience and 1 million euros of development investment as of 2009.

• NAHUAL experience is applicable to other telescopes, such as CARMENES @ Calar Alto.