Persona: López Heredero, Raquel
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López Heredero
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Publicación Acceso Abierto The Imaging Magnetograph eXperiment (IMaX) for the Sunrise Balloon-Borne Solar Observatory(Springer Link, 2011-01-17) Martínez Pillet, V.; Del Toro Iniesta, J. C.; Álvarez Herrero, A.; Domingo, V.; Bonet Navarro, J. A.; González Fernández, C.; López Jiménez, A. C.; Pastor, C.; Gasent Blesa, J. L.; Mellado, P.; Piqueras, J.; Aparicio, B.; Balaguer, M.; Ballesteros, E.; Belenguer Dávila, T.; Bellot Rubio, L. R.; Berkefeld, T.; Collados Vera, Manuel; Deutsch, W.; Feller, A.; Girela, F.; Grauf, B.; López Heredero, Raquel; Herranz, M.; Jerónimo, J. M.; Laguna, H.; Meller, R.; Menéndez, M.; Morales, R.; Orozco Suárez, D.; Ramos, G.; Reina, M.; Ramos, J. L.; Rodríguez, P.; Sánchez, A.; Uribe Patarroyo, N.; Barthol, P.; Gandorfer, A.; Knoelker, M.; Schmidt, Walter; Solanki, S. K.; Vargas Domínguez, S.; Ministerio de Ciencia e Innovación (MICINN); Deutsches Zentrum für Luft- und Raumfahrt (DLR); National Aeronautics and Space Administration (NASA); López Heredero, R. [0000-0002-2197-8388]; López Jiménez, A. [0000-0002-6297-0681]; Balaguer, M. [0000-0003-4738-7727]; Del Toro Iniesta, J. C. [0000-0002-3387-026X]; Reina Aranda, M. [0000-0003-0248-2771]; Álvarez Herrero, A. [0000-0001-9228-3412]; Herranz de la Revilla, M. L. [0000-0003-4343-6632]; Morales Muñoz, R. [0000-0003-1661-0594]; Pastor, C. [0000-0001-9631-9558]; Gasent Blesa, J. L. [0000-0002-1225-4177]; Collados, M. [0000-0002-6210-9648]; Jerónimo, J. M. [0000-0002-4944-5823]; Bellot Rubio, L. R. [0000-0001-8669-8857]; Martínez Pillet, V. [0000-0001-7764-6895]The Imaging Magnetograph eXperiment (IMaX) is a spectropolarimeter built by four institutions in Spain that flew on board the Sunrise balloon-borne solar observatory in June 2009 for almost six days over the Arctic Circle. As a polarimeter, IMaX uses fast polarization modulation (based on the use of two liquid crystal retarders), real-time image accumulation, and dual-beam polarimetry to reach polarization sensitivities of 0.1%. As a spectrograph, the instrument uses a LiNbO3 etalon in double pass and a narrow band pre-filter to achieve a spectral resolution of 85 mÅ. IMaX uses the high-Zeeman-sensitive line of Fe I at 5250.2 Å and observes all four Stokes parameters at various points inside the spectral line. This allows vector magnetograms, Dopplergrams, and intensity frames to be produced that, after reconstruction, reach spatial resolutions in the 0.15 – 0.18 arcsec range over a 50×50 arcsec field of view. Time cadences vary between 10 and 33 s, although the shortest one only includes longitudinal polarimetry. The spectral line is sampled in various ways depending on the applied observing mode, from just two points inside the line to 11 of them. All observing modes include one extra wavelength point in the nearby continuum. Gauss equivalent sensitivities are 4 G for longitudinal fields and 80 G for transverse fields per wavelength sample. The line-of-sight velocities are estimated with statistical errors of the order of 5 – 40 m s−1. The design, calibration, and integration phases of the instrument, together with the implemented data reduction scheme, are described in some detail.Publicación Restringido Micromachined optical fiber current sensor(OSA (The Optical Society) Publishing, 1999-09-01) López Heredero, Raquel; Fernández de Caleya, R. F.; Guerrero, H.; Los Santos, P.; Cruz Acero, M.; Esteve, J.; 0000-0002-2197-8388; 0000-0001-9440-7984; 0000-0003-2922-3489; 0000-0002-2131-1081We describe a micromachined optical fiber current sensor. The sensing element consists of a squared silicon membrane (8 mm long and 20 µm thick) that has a cylindrical permanent magnet (NdFeB alloy, 3-mm diameter, 1.5 mm high) fixed on its central region. This structure allows the permanent magnet to vibrate in the presence of the magnetic field gradient generated by an ac. A linear relation between the electrical current and the magnet displacement was measured with white-light interferometry with an optical fiber low-finesse Fabry–Perot microcavity. A measurement range of 0–70 A and a minimum detectable intensity of 20 mA were obtained when distance D between the membrane and the electrical power line was 5 mm. The output signal directly shows a linear response with distance D.Publicación Acceso Abierto The EChO science case(Springer Link, 2015-11-29) Tinetti, G.; Drossart, P.; Eccleston, P.; Hartogh, P.; Isaak, K.; Linder, M.; Lovis, C.; Micela, G.; Olliver, M.; Puig, L.; Ribas, I.; Sicardy, B.; Kehoe, T.; Deeg, H.; Petrov, R.; Doel, P.; Tennyson, J.; Filacchione, G.; Varley, R.; Temple, J.; Lahav, O.; MacTavish, C.; Wisniowski, T.; Piccioni, G.; Guàrdia, J.; Cavarroc, C.; Jones, G.; Ade, P.; Sanromá, E.; Frith, J.; Lognonné, P.; Pantin, E.; Crook, J.; Colomé, J.; Allard, F.; Azzollini, R.; Burston, R.; Parviainen, H.; Malaguti, G.; Gerard, J. C.; Stamper, R.; Barrado, D.; Maldonado, J.; Morales, J. C.; Yurchenko, S. N.; Lagage, P. O.; Prinja, R.; Koskinen, T.; Waldmann, I.; Venot, O.; Heiter, U.; Lim, T.; Pace, E.; Moya Bedon, A.; Irwin, P.; Michaut, C.; Monteiro, M.; Jones, H.; Wawer, P.; Fouqué, P.; Widemann, T.; Alonso Floriano, F. J.; Eiroa, C.; Savini, G.; Stixrude, L.; Damasso, M.; Rataj, M.; Glasse, A.; Koskinen, T.; Bulgarelli, A.; Ciaravella, A.; Hollis, M.; Schmider, F. X.; Kerschbaum, F.; Licandro Goldaracena, J.; Claret, A.; Rocchetto, M.; López Valverde, Miguel Ángel; Fossey, S.; Leto, G.; Ramos Zapata, G.; Beaulieu, J. P.; Balado, A.; Luzzi, D.; Rebordao, J.; Encrenaz, T.; Adriani, A.; Alcala, J.; Guedel, M.; Morales Calderón, M.; Peña Ramírez, K. Y.; Herrero, Enrique; Focardi, M.; Montalto, M.; Wright, G.; Danielski, C.; Burleigh, M. R.; Medvedev, A.; Murgas Alcaino, F.; Chadney, J.; Bowles, N.; Maxted, Pierre; Kerschbaum, F.; Ward Thompson, D.; Laken, B.; Börne, P.; Christian Jessen, N.; Dominic, C.; López Morales, M.; Miles Paez, P.; Achilleos, N.; Biondi, D.; White, G.; López Heredero, Raquel; De Kok, R.; Frith, J.; Grodent, D.; Rank Lüftinger, T.; Scholz, A.; Villaver, E.; Dobrijévic, M.; Alard, C.; Demangeon, O. D. S.; De Witt, J.; Machado, P.; Cordier, D.; Charnoz, S.; Rodler, F.; Gerard, J. C.; Sousa, S. G.; Viti, S.; Cole, R.; Blecka, M.; Barber, R. J.; Middleton, K.; Griffin, M.; Giro, E.; Cho, J.; Covino, E.; Turrini, D.; Moro Martín, A.; Decin, L.; Ramos, A. A.; Schrader, J. R.; Massi, F.; Abe, L.; Mauskopf, P.; Batista, V.; Agnor, C.; Bordé, P.; Fabrizio, N.; Bakos, G.; Rengel, M.; Gustin, J.; Hueso, R.; Fernández Hernández, Maite; Ray, T.; Claudi, R.; Femenía Castella, B.; Rebolo, R.; Sethenadh, J.; Luntzer, A.; Mueller Wodarg, I.; Delgado Mena, E.; Brown, L.; De Sio, A.; González Hernández, J.; Selsis, F.; Leconte, J.; Del Vecchio, C.; Budaj, J.; Scandariato, G.; Pagano, I.; García Piquer, A.; Guillot, T.; Terenzi, L.; Tabernero, H. M.; Forget, F.; Hargrave, P.; North, C.; Heyrovsky, D.; Cerulli, R.; Adybekian, V.; Read, P.; Pinsard, Frederic; Parmentier, V.; Collura, A.; Hubert, B.; Lanza, N.; Graczyk, R.; Fouqué, P.; Giuranna, M.; Valdivieso, M. L.; Pérez Hoyos, S.; Andersen, A.; Mall, U.; Buchhave, L. A.; Yelle, R.; Rickman, H.; Ballerini, P.; Affer, L.; Maruquette, J. B.; Sánchez Béjar, V. J.; Nelson, Richard; Fletcher, L.; Radioti, A.; Turrini, D.; Montes, D.; Gizon, L.; Galand, M.; Gómez, H.; Eymet, V.; Esposito, M.; Smith, A.; Morello, G.; Allende Prieto, C.; Justtanot, K.; Bryson, I.; Pallé, E.; Amado, P. J.; Figueira, P.; Shore, Steven; Focardi, M.; Strazzulla, G.; Giani, E.; Pietrzak, R.; González Merino, B.; Lo Cicero, Ugo; Gaulme, P.; Sozzetti, A.; Femenía Castella, B.; Maillard, J. P.; Cabral, A.; Iro, N.; Magnes, W.; Pinfield, David J.; Swain, M.; Showman, A.; Bellucci, G.; Kerins, E.; Maurin, A. S.; Poretti, E.; Boisse, I.; Barton, E. J.; Kervella, P.; Guio, P.; Norgaard Nielsen, H. U.; Bézard, B.; Montañés Rodríguez, P.; Banaszkiewicz, M.; Kovács, G.; Baffa, C.; Del Val Borro, M.; Belmonte Avilés, J. A.; Palla, F.; Hersant, F.; Correira, A.; Yung, Y.; Cockell, Charles S.; Vinatier, S.; Pilat Lohinger, E.; Krupp, N.; Orton, G.; Vakili, F.; Pezzuto, S.; Di Giorgio, A.; Waltham, D.; Testi, L.; Stiepen, A.; Deroo, P.; Capria, M. T.; Eales, S.; Irshad, R.; Stolarski, M.; Zapatero Osorio, M. R.; Swinyard, B.; Griffith, C.; Winek, W.; Bouy, H.; Thompson, S.; Maggio, A.; Moses, J.; Liu, S. J.; Lithgow Bertelloni, C.; Coudé du Foresto, V.; Martín Torres, Javier; Fletcher, L.; Barlow, M.; Coustenis, A.; Berry, D.; López Puertas, M.; Banaszkiewicz, M.; Lundgaard Rasmussen, I.; Hoogeveen, Ruud; Morais, H.; Watkins, C.; Oliva, E.; Scuderi, S.; Aylward, A.; Bonford, B.; Sitek, P.; Haigh, J.; Prisinzano, L.; Soret, L.; Wawrzaszk, A.; Lammer, H.; Figueira, P.; Gianotti, F.; Readorn, K.; Tanga, P.; Israelian, G.; Gesa, L.; Peralta, J.; Gómez Leal, I.; Cassan, A.; Tecsa, M.; Tessenyi, M.; Pancrazzi, M.; Coates, A.; Gambicorti, L.; Gear, W.; Winter, B.; Piskunov, N.; Álvarez Iglesias, C. A.; Polichtchouk, I.; Altieri, F.; Ottensamer, R.; Watson, D.; Rezac, L.; Vandenbussche, B.; Waters, R.; Dorfi, E.; Morgante, G.; Pascale, E.; Hornstrup, A.; Snellen, Ignas; Lodieu, N.; Lellouch, E.; Espinoza Contreras, M.; Jarchow, C.; Agúndez, Marcelino; Filacchione, G.; Abreu, M.; Grassi, D.; Tingley, B. W.; Sánchez Lavega, Agustín; Tozzi, A.; Sanz Forcada, J.; Kipping, D.; Chamberlain, S.; Trifoglio, M.; Barstow, J. K.; Santos, Nuno C.; Gillon, M.; Hébrard, E.; Cecchi Pestellini, C.; Fossey, S.; García López, Ramón; Thrastarson, H.; Rees, J. M.; Selig, A.; Galand, M.; Jacquemoud, S.; Branduardi Raymont, Graziella; Rebordao, J. [0000-0002-7418-0345]; Kerschbaum, F. [0000-0001-6320-0980]; Abreu, M. [0000-0002-0716-9568]; Tabernero, H. [0000-0002-8087-4298]; López Puertas, M. [0000-0003-2941-7734]; Jacquemoud, S. [0000-0002-1500-5256]; Tennyson, J. [0000-0002-4994-5238]; Focardi, M. [0000-0002-3806-4283]; Leto, G. [0000-0002-0040-5011]; Lodieu, N. [0000-0002-3612-8968]; Tinetti, G. [0000-0001-6058-6654]; Danielski, C. [0000-0002-3729-2663]; Hornstrup, A. [0000-0002-3363-0936]; Kervella, P. [0000-0003-0626-1749]; Sánchez Bejar, V. [0000-0002-5086-4232]; López Heredero, R. [0000-0002-2197-8388]; Sanz Forcada, J. [0000-0002-1600-7835]; Rickman, H. [0000-0002-9603-6619]; Maggio, A. [0000-0001-5154-6108]; Medved, A. [0000-0003-2713-8977]; Tinetti, G. [0000-0001-6058-6654]; Fletcher, L. [0000-0001-5834-9588]; Haigh, J. [0000-0001-5504-4754]; Bakos, G. [0000-0001-7204-6727]; Stixrude, L. [0000-0003-3778-2432]; Amado, P. J. [0000-0002-8388-6040]; Martín Torres, J. [0000-0001-6479-2236]; Correira, A. [0000-0002-8946-8579]; Yurchenko, S. [0000-0001-9286-9501]; Rataj, M. [0000-0002-2978-9629]; Guedel, M. [0000-0001-9818-0588]; Piskunov, N. [0000-0001-5742-7767]; Filacchione, G. [0000-0001-9567-0055]; Adibekyan, V. [0000-0002-0601-6199]; Budaj, J. [0000-0002-9125-7340]; Poretti, E. [0000-0003-1200-0473]; Pascale, E. [0000-0002-3242-8154]; Claudi, R. [0000-0001-7707-5105]; Piccioni, G. [0000-0002-7893-6808]; Ribas, I. [0000-0002-6689-0312]; Sanroma, E. [0000-0001-8859-7937]; Agundez, M. [0000-0003-3248-3564]; Montes, D. [0000-0002-7779-238X]; Lognonne, P. [0000-0002-1014-920X]; Abreu, M. [0000-0002-0716-9568]; Montes, D. [0000-0002-7779-238X]; Morais, M. H. [0000-0001-5333-2736]; Tanga, P. [0000-0002-2718-997X]; Peralta, J. [0000-0002-6823-1695]; Hueso, R. [0000-0003-0169-123X]; Leto, G. [0000-0002-0040-5011]; Morales, J. C. [0000-0003-0061-518X]; Pérez Hoyos, S. [0000-0002-2587-4682]; Santos, N. [0000-0003-4422-2919]; Lithgow Bertelloni, C. [0000-0003-0924-6587]; Delgado, M. E. [0000-0003-4434-2195]; Barlow, M. [0000-0002-3875-1171]; Deeg, H. [0000-0003-0047-4241]; Bouy, H. [0000-0002-7084-487X[; Grassi, D. [0000-0003-1653-3066]; Figueira, P. [0000-0001-8504-283X]; Barton, E. [0000-0001-5945-9244]; Coates, A. [0000-0002-6185-3125]; García Ramón, J. [0000-0002-8204-6832]; Watson, D. [0000-0002-4465-8264]; Morales Calderon, M. [0000-0001-9526-9499]; Demangeon, O. [0000-0001-7918-0355]; Ray, T. [0000-0002-2110-1068]; Guio, P. [0000-0002-1607-5862]; Gillon, M. [0000-0003-1462-7739]; Bulgarelli, A. [0000-0001-6347-0649]; Prisinzano, L. [0000-0002-8893-2210]; Barstow, J. [0000-0003-3726-5419]; Pancrazzi, M. [0000-0002-3789-2482]; Barrado Navascues, D. [0000-0002-5971-9242]; Balado, A. [0000-0003-4268-2516]; Malaguti, G. [0000-0001-9872-3378]; Zapatero Osorio, M. R. [0000-0001-5664-2852]; Affer, L. [0000-0001-5600-3778]; Ciaravella, A. [0000-0002-3127-8078]; Guillot, T. [0000-0002-7188-8428]; Altieri, F. [0000-0002-6338-8300]; Covino, E. [0000-0002-6187-6685]; Venot, O. [0000-0003-2854-765X]; López Valverde, M. A. [0000-0002-7989-4267]; Cabral, A. [0000-0002-9433-871X]; Selsis, F. [0000-0001-9619-5356]; Turrini, D. [0000-0002-1923-7740]; Ward Thompson, D. [0000-0003-1140-2761]; Rebolo, R. [0000-0003-3767-7085]; Damasso, M. [0000-0001-9984-4278]; Tizzi, A. [0000-0002-6725-3825]; Morgante, G. [0000-0001-9234-7412]; Pena Ramírez, K. [0000-0002-5855-401X]; Galand, M. [0000-0001-5797-914X]; Pace, E. [0000-0001-5870-1772]; Pilat Lohinger, E. [0000-0002-5292-1923]; Sánchez Lavega, A. [0000-0001-7234-7634]; Waldmann, I. [0000-0002-4205-5267]; Claret, A. [0000-0002-4045-8134]; Olivia, E. [0000-0002-9123-0412]; Kovacs, G. [0000-0002-2365-2330]; Gómez, H. [0000-0003-3398-0052]; Monteiro, M. [0000-0001-5644-0898]; Bellucci, G. [0000-0003-0867-8679]; Baffa, C. [0000-0002-4935-100X]; Scholz, A. [0000-0001-8993-5053]; Bezard, B. [0000-0002-5433-5661]; Scuderi, Salvatore [0000-0002-8637-2109]; Hersant, F. [0000-0002-2687-7500]; Maldonado, J. [0000-0002-4282-1072]; Gear, W. [0000-0001-6789-6196]; Sousa, S. [0000-0001-9047-2965]; Irwin, P. [0000-0002-6772-384X]; Pinfield, D. [0000-0002-7804-4260]; Kipping, D. [0000-0002-4365-7366]; Ade, P. [0000-0002-5127-0401]; Vandenbussche, B. [0000-0002-1368-3109]; Burleigh, M. [0000-0003-0684-7803]; Chadney, J. [0000-0002-5174-2114]; Moro Martín, A. [0000-0001-9504-8426]; Scandariato, G. [0000-0003-2029-0626]; Rodríguez, P. [0000-0002-6855-9682]; Maldonado, J. [0000-0002-2218-5689]; Michaut, C. [0000-0002-2578-0117]; Pérez Hoyos, S. [0000-0001-9797-4917]The discovery of almost two thousand exoplanets has revealed an unexpectedly diverse planet population. We see gas giants in few-day orbits, whole multi-planet systems within the orbit of Mercury, and new populations of planets with masses between that of the Earth and Neptune—all unknown in the Solar System. Observations to date have shown that our Solar System is certainly not representative of the general population of planets in our Milky Way. The key science questions that urgently need addressing are therefore: What are exoplanets made of? Why are planets as they are? How do planetary systems work and what causes the exceptional diversity observed as compared to the Solar System? The EChO (Exoplanet Characterisation Observatory) space mission was conceived to take up the challenge to explain this diversity in terms of formation, evolution, internal structure and planet and atmospheric composition. This requires in-depth spectroscopic knowledge of the atmospheres of a large and well-defined planet sample for which precise physical, chemical and dynamical information can be obtained. In order to fulfil this ambitious scientific program, EChO was designed as a dedicated survey mission for transit and eclipse spectroscopy capable of observing a large, diverse and well-defined planet sample within its 4-year mission lifetime. The transit and eclipse spectroscopy method, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allows us to measure atmospheric signals from the planet at levels of at least 10−4 relative to the star. This can only be achieved in conjunction with a carefully designed stable payload and satellite platform. It is also necessary to provide broad instantaneous wavelength coverage to detect as many molecular species as possible, to probe the thermal structure of the planetary atmospheres and to correct for the contaminating effects of the stellar photosphere. This requires wavelength coverage of at least 0.55 to 11 μm with a goal of covering from 0.4 to 16 μm. Only modest spectral resolving power is needed, with R ~ 300 for wavelengths less than 5 μm and R ~ 30 for wavelengths greater than this. The transit spectroscopy technique means that no spatial resolution is required. A telescope collecting area of about 1 m2 is sufficiently large to achieve the necessary spectro-photometric precision: for the Phase A study a 1.13 m2 telescope, diffraction limited at 3 μm has been adopted. Placing the satellite at L2 provides a cold and stable thermal environment as well as a large field of regard to allow efficient time-critical observation of targets randomly distributed over the sky. EChO has been conceived to achieve a single goal: exoplanet spectroscopy. The spectral coverage and signal-to-noise to be achieved by EChO, thanks to its high stability and dedicated design, would be a game changer by allowing atmospheric composition to be measured with unparalleled exactness: at least a factor 10 more precise and a factor 10 to 1000 more accurate than current observations. This would enable the detection of molecular abundances three orders of magnitude lower than currently possible and a fourfold increase from the handful of molecules detected to date. Combining these data with estimates of planetary bulk compositions from accurate measurements of their radii and masses would allow degeneracies associated with planetary interior modelling to be broken, giving unique insight into the interior structure and elemental abundances of these alien worlds. EChO would allow scientists to study exoplanets both as a population and as individuals. The mission can target super-Earths, Neptune-like, and Jupiter-like planets, in the very hot to temperate zones (planet temperatures of 300–3000 K) of F to M-type host stars. The EChO core science would be delivered by a three-tier survey. The EChO Chemical Census: This is a broad survey of a few-hundred exoplanets, which allows us to explore the spectroscopic and chemical diversity of the exoplanet population as a whole. The EChO Origin: This is a deep survey of a subsample of tens of exoplanets for which significantly higher signal to noise and spectral resolution spectra can be obtained to explain the origin of the exoplanet diversity (such as formation mechanisms, chemical processes, atmospheric escape). The EChO Rosetta Stones: This is an ultra-high accuracy survey targeting a subsample of select exoplanets. These will be the bright “benchmark” cases for which a large number of measurements would be taken to explore temporal variations, and to obtain two and three dimensional spatial information on the atmospheric conditions through eclipse-mapping techniques. If EChO were launched today, the exoplanets currently observed are sufficient to provide a large and diverse sample. The Chemical Census survey would consist of > 160 exoplanets with a range of planetary sizes, temperatures, orbital parameters and stellar host properties. Additionally, over the next 10 years, several new ground- and space-based transit photometric surveys and missions will come on-line (e.g. NGTS, CHEOPS, TESS, PLATO), which will specifically focus on finding bright, nearby systems. The current rapid rate of discovery would allow the target list to be further optimised in the years prior to EChO’s launch and enable the atmospheric characterisation of hundreds of planets.Publicación Restringido Steam-Resistant Optical Materials for Use in Diagnostic Mirrors for ITER(Institute of Electrical and Electronics Engineers, 2020-01-30) Pereira, A.; Martín, P.; López Heredero, Raquel; Torquemada, M. C.; Rodrigo, M. T.; Gómez, L. J.; Vila, R.; Belenguer Dávila, T.; Medrano, M.; Piqueras, J. J.; Le Guern, F.; Pastor, C.; Rodríguez, M. C.; Quintana, J. A.; Carrasco, R.; Lapayese, F.; De la Peña, A.; Alén Cordero, C.; Pereira, A. [0000-0001-7945-6569]The need for a steam ingress environmental experiment is very significant to understand the impact of accidental in-vessel coolant leaks at ITER and to study the exposure of optical diagnostics to steam and humid conditions. This could happen as a result of the damage to the cooling pipes due to runaway electrons generated during plasma disruptions in ITER. In order to know the scope of this potential impact, an assessment was carried out to simulate and to study the exposure of optical elements to strong and hostile moisture conditions. After test, different measurements on optical mirrors were performed to characterize the reflectance properties, observed both in the visible and infrared spectral ranges, as well as the analysis of wavefront error, coating adherence test, and X-ray spectroscopy. Modification of properties and fluctuations in the physical behavior of optical materials and components were observed. Substrates and coatings were affected at different levels due to corrosion and oxidative depositions that modify their optical performances. In general, there are large differences in the results obtained for the same material manufactured by different manufacturing processes. Steam and humidity affected, especially substrates and metal coatings. Substrates made of silicon carbide and stainless steel were the least affected by corrosion. Rhodium coating suffered less damage than the molybdenum coating.Publicación Acceso Abierto Effect of Low-Doses of Gamma Radiation on Electric Arc-Induced Long Period Fiber Gratings(Multidisciplinary Digital Publishing Institute (MDPI), 2021-03-26) Mesonero Santos, P.; Fernández Medina, A.; Coelho, L. C. C.; Viveiros, D.; Jorge, P. A.; Belenguer Dávila, T.; López Heredero, Raquel; Mesonero Santos, P. [0000-0002-6088-5731]; Fernández Medina, A. [0000-0002-1232-4315]; Coelho, L. C. C. [0000-0001-6205-9479]; Jorge, P. A. [0000-0003-1484-2068]; López Heredero, R. [0000-0002-2197-8388]This work presents an experimental study on the effects of gamma radiation on Long Period Fiber Gratings (LPFGs) in a low-dose test campaign to evaluate their eventual degradation. The study was carried out with standard single-mode fibers where the grating was inscribed using the Electric-Arc Discharge (EAD) technique. Before the gamma campaign, a detailed optical characterization was performed with repeatability tests to verify the accuracy of the setup and the associated error sources. The gamma-induced changes up to a dose of 200 krad and the recovery after radiation were monitored with the Dip Wavelength Shift (DWS). The results show that the gamma sensitivity for a total dose of 200 krad is 11 pm/krad and a total DWS of 2.3 nm has been observed with no linear dependence. Post-radiation study shows that recovery from radiation-induced wavelength shift is nearly complete in about 4000 h. Experimental results show that the changes suffered under gamma irradiation of these LPFGs are temporary making them a good choice as sensors in space applications.Publicación Restringido Fiber Bragg gratings for optical sensing (FIBOS) for an aerospace application(SPIE Optical Engineering Applications, 2010-09-09) López Heredero, Raquel; Frövel, Malte; Laguna, H.; Anderson, A.; Garranzo García, D.; Belenguer Dávila, T.; Frövel, M. [0000-0001-9447-4036]; López Heredero, R. [0000-0002-2197-8388]FIBOS, as one of the payloads of a picosatellite called OPTOS, will be used to measure temperature during the mission with Fiber Bragg Gratings. Description and calibration of FIBOS are presented.Publicación Acceso Abierto The Complex Molecules Detector (CMOLD): A Fluidic-Based Instrument Suite to Search for (Bio)chemical Complexity on Mars and Icy Moons(Mary Ann Liebert Publishers, 2020-09-15) Fairén, Alberto G.; Gómez Elvira, J.; Briones, C.; Prieto-Ballesteros, Olga; Rodríguez Manfredi, J. A.; López Heredero, Raquel; Belenguer Dávila, T.; Moral, A.; Moreno Paz, Mercedes; Parro, Víctor; European Research Council (ERC); Agencia Estatal de Investigación (AEI); Briones, C. [0000-0003-2213-8353]; Prieto Ballesteros, O. [0000-0002-2278-1210]; López Heredero, R. [0000-0002-2197-8388]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737Organic chemistry is ubiquitous in the Solar System, and both Mars and a number of icy satellites of the outer Solar System show substantial promise for having hosted or hosting life. Here, we propose a novel astrobiologically focused instrument suite that could be included as scientific payload in future missions to Mars or the icy moons: the Complex Molecules Detector, or CMOLD. CMOLD is devoted to determining different levels of prebiotic/biotic chemical and structural targets following a chemically general approach (i.e., valid for both terrestrial and nonterrestrial life), as well as their compatibility with terrestrial life. CMOLD is based on a microfluidic block that distributes a liquid suspension sample to three instruments by using complementary technologies: (1) novel microscopic techniques for identifying ultrastructures and cell-like morphologies, (2) Raman spectroscopy for detecting universal intramolecular complexity that leads to biochemical functionality, and (3) bioaffinity-based systems (including antibodies and aptamers as capture probes) for finding life-related and nonlife-related molecular structures. We highlight our current developments to make this type of instruments flight-ready for upcoming Mars missions: the Raman spectrometer included in the science payload of the ESAs Rosalind Franklin rover (Raman Laser Spectrometer instrument) to be launched in 2022, and the biomarker detector that was included as payload in the NASA Icebreaker lander mission proposal (SOLID instrument). CMOLD is a robust solution that builds on the combination of three complementary, existing techniques to cover a wide spectrum of targets in the search for (bio)chemical complexity in the Solar System.Publicación Acceso Abierto In-orbit demonstration of fiber optic sensors based on Bragg gratings(International Conference on Space Optics, 2019-07-12) López Heredero, Raquel; Frövel, Malte; Laguna, H.; Belenguer Dávila, T.; Instituto Nacional de Técnica Aeroespacial (INTA); López Heredero, R. [0000000221978388]; Frövel, M. [00000000194474036]FIBOS (FIber Bragg gratings for Optical Sensing) is one payload used to monitor temperature and strain during a nanosatellite mission. Description of the payload and in-orbit results are presented. Fiber Bragg Grating (FBG) sensors offer attractive and robust solutions for temperature and pressure monitoring in a spacecraft. Moreover, they can be embedded in composite structures or attached on their surface for structural health monitoring during the entire life cycle of a satellite, from integration and qualification tests, to final operation. FIBOS contains two FBGs to measure temperature and strain during one space mission called OPTOS. The mission, developed by INTA (Instituto Nacional de Técnica Aeroespacial), was a low-cost nanosatellite based on a triple configuration (3U) of the popular Cubesat standard. OPTOS was launched in November 2013 and was operative during two years. Its main goal was to validate and demonstrate the suitability of novel technologies for space applications inside a miniaturized area with big restrictions in terms of mass and power consumption. This work describes the payload components. FIBOS contains commercial off-the-shelf (COTS) parts like a monolithic tunable laser and a conventional InGaAs pigtailed photodiode. The optical sensor head includes two FBGs mounted onto a steel mechanical structure to monitor temperature and strain. Results of the mission are presented. Measurements performed during the operation in-orbit show good agreement with calibration data performed on earth inside a thermalvacuum chamber (TVC). This paper shows a demonstration of a fiber optic sensor based on FBGs in space environment.Publicación Restringido Comparisons of tin depth profile analyses in float glass(Elsevier BV, 1998-03-11) Townsend, P. D.; Can, N.; Chandler, P. J.; Farmery, B. W.; López Heredero, Raquel; Peto, A.; Salvin, L.; Underdown, D.; Yang, C.; 0000-0002-2197-8388Data are presented showing the profile of tin diffusion during the production of float glass, by measuring non-destructively the refractive index profiles in the diffused layer. The optical waveguide modes give unequivocal evidence for an anomaly in the tin depth distribution. The results are compared with those from sectioning techniques, used in depth profiles determined by ion beam analyses and cathodoluminescence (CL). There is agreement between these methods which confirm the presence of a maximum in the tin concentration below the surface which had been in contact with the tin bath (this had been linked by Mössbauer data to a rise in the Sn4+ concentration). The ion beam analyses record different depth profiles for Si, Na and Ca. The Sn4+ feature increases the refractive index, as does the diffusion of Sn2+. The index becomes constant at large tin concentrations. We suggest that Sn4+ is linked to CL emission at 2.68 eV and Sn2+ to the 1.97 eV CL emission. Iron impurities give a 1.73 eV signal. Contrary to earlier suggestions, we propose that the luminescence associated with the presence of tin arises from intrinsic defects stabilised by the tin, not from tin acting directly as a luminescence site.Publicación Restringido Micromachined low-finesse Fabry-Perot interferometer for the measurement of DC and AC electrical currents(Institute of Electrical and Electronics Engineers, 2003-04-22) López Heredero, Raquel; Santos, J. L.; Fernández de Caleya, R. F.; Guerrero, H.; López Heredero, R. [0000-0002-2197-8388]; Guerrero, H. [0000-0003-2922-3489]; Santos, J. L. [0000-0002-0818-4268]A micromachined low finesse Fabry-Perot interferometer for measuring DC and AC electrical current is presented. Interrogation of the microcavity is achieved by a dual-wavelength fiber Bragg grating technique working in quadrature. A linear relation between the DC electrical current and the optical phase defined by the microcavity was detected. Large enhancement of the sensitivity of the microcavities is presented with the use of a planar coil instead of a power line. The sensitivity of the sensor with the planar coil configuration is 7.9 rad/A and resolution of ∼0.18 mA//spl radic/Hz is achieved when the distance between the planar coil and the transducer head is 2 mm. The response of the sensor for AC measurements is 0.14 V/A with a resolution of 6 mA//spl radic/Hz when the distance between the power line and the transducer head is 5.5 cm.
