I. Furniss - Academia.edu (original) (raw)

Papers by I. Furniss

The first detection of thermal water emission from a Herbig-Haro object is presented. The observa... more The first detection of thermal water emission from a Herbig-Haro object is presented. The observations were performed with the Lws (Long Wavelength Spectrograph) aboard Iso (Infrared Space Observatory). Besides H 2 O, rotational lines Key words: stars: formation-ISM: molecules-ISM: jets and outflows-ISM: individual objects: HH 54-physical processes: shock waves-physical processes: radiative transfer ? Based on observations with Iso,anEsa project with instruments funded by Esa Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of Isas and Nasa (see: Kessler et al. 1996).

Abstract. Grating spectra, covering the wavelength range 45 to stellar objects (S 140 IRS1, 2, 3)... more Abstract. Grating spectra, covering the wavelength range 45 to stellar objects (S 140 IRS1, 2, 3) with IRS 1 being a bipolar out1 87~ am have been taken with the ISO Long Wavelength Spec-flow source embedded in the cloud behind the ionisation front

Abstract. An unusually intense energetic proton precipita-tion event occurredon 26 November2000. ... more Abstract. An unusually intense energetic proton precipita-tion event occurredon 26 November2000. The resulting sur-face brightness of Hydrogen beta amounted to several hun-dred Rayleighs. This made it possible to examine the lineproﬁle at 1.3 A resolution in 60 s exposures for several hours˚in the magnetic zenith, a combination of spectral and tempo-ral resolution not previously achieved. We conﬁrm the ex-istence of a signiﬁcant red-shifted component, the result ofupward ﬂowing emitting hydrogen atoms. The N ﬁlter showed, in addition to the nitrogen ion band, several 1N (1,3)lines of the atomic oxygen ion of the ( P– D) multiplet 1.The Doppler proﬁle indicates that the incident proton spec-trum must have been in the range of a few hundred eV toperhaps a few keV energy,a conjecturecorroboratedby near-coincident (in time and space) measurements of proton spec-tra from the DMSP F12 and FAST satellites. 1 Introduction A new instrumental platform has been installed at Longyear-byen onSva...

The Long-Wavelength Spectrometer (LWS) is one of two complementary spectrometers aboard the Europ... more The Long-Wavelength Spectrometer (LWS) is one of two complementary spectrometers aboard the European Space Agency's Infrared Space Observatory 1 (ISO) (Kessler et al., 1996). It operates over the wavelength range 43 196:9 m at either medium (about 150 to 200) or high (6800 to 9700) spectral resolving power. This Letter describes the instrument and its modes of operation; a companion paper (Swinyard et al, 1996) describes its performance and calibration.

Annales Geophysicae, 2003

Measurements in the visible wavelength range at high spectral resolution (1.3Å) have been made at... more Measurements in the visible wavelength range at high spectral resolution (1.3Å) have been made at Longyearbyen, Svalbard (15.8 E,78.2 N) during an interval of intense proton precipitation. The shape and Doppler shift of hydrogen Balmer beta line profiles have been compared with model line profiles, using as input ion energy spectra from almost coincident passes of the FAST and DMSP spacecraft. The comparison shows that the simulation contains the important physical processes that produce the profiles, and confirms that measured changes in the shape and peak wavelength of the hydrogen profiles are the result of changing energy input. This combination of high resolution measurements with modeling provides a method of estimating the incoming energy and changes in flux of precipitating protons over Svalbard, for given energy and pitch-angle distributions. Whereas for electron precipitation, information on the incident particles is derived from brightness and brightness ratios which require at least two spectral windows, for proton precipitation the Doppler profile of resulting hydrogen emission is directly related to the energy and energy flux of the incident energetic protons and can be used to gather information about the source region. As well as the expected Doppler shift to shorter wavelengths, the measured profiles have a significant red-shifted component, the result of upward flowing emitting hydrogen atoms.

Monthly Notices of the Royal Astronomical Society, 1984

Monthly Notices of the Royal Astronomical Society, 1983

Monthly Notices of the Royal Astronomical Society, 1982

Monthly Notices of the Royal Astronomical Society, 1984

We report ISO-LWS observations toward the low mass star IRAS16293-2422 between 43µm - 197µm. The ... more We report ISO-LWS observations toward the low mass star IRAS16293-2422 between 43µm - 197µm. The CO, H 2 O and OH rotational lines and the OI(63µm) fine-structure line dominate the spectrum. Combining the CO J up =14 to 25 observations with previous J up =6 measurements, we derive stringent limits on the density (~3 · 10 4 cm -3 ), temperature (~1500 K), and column density (~1.5 · 10 20 cm -2 ) of the emitting gas. We show that this warm gas is associated with the outflow and that a low velocity, C-type shock can account for the characteristics of the CO spectrum. The H 2 O and OH abundances derived from the observed line fluxes are [H 2 O] / [H 2 ] ~2 · 10 -5 and [OH] / [H 2 ] ~5 · 10 -6 respectively. Finally, we speculate that the OI(63µm) line emission originates in the collapsing envelope that surrounds the central object.

We present an ISO Long Wavelength Spectrometer (LWS) grating spectrum of the carbon-rich circumst... more We present an ISO Long Wavelength Spectrometer (LWS) grating spectrum of the carbon-rich circumstellar envelope -CSE- of IRC+10216 between 43 and 197μm. The spectrum consists of strong dust emission plus a forest of emission lines from CO, HCN, H^13^CN and vibrationally excited HCN (ν_2_=1^1^,2^0,2^ and ν_1,3_=1). All the CO lines between J=14-13 and J=39-38 have been detected while lines of HCN with J_u_ as high as 48 have also been observed. The molecular emission arises from the warm and dense gas located in the innermost zone of the CSE. The CO and HCN emission can be easily explained if the vibrational and rotational temperatures are around 700-1500 K. We also report the tentative detection of the bending mode of the C_3_ molecule around 62cm^-1^ (157.2μm).

The wavelength and flux calibration, and the inorbit performance of the Infrared Space Observator... more The wavelength and flux calibration, and the inorbit performance of the Infrared Space Observatory Long-Wavelength Spectrometer (LWS) are described. The LWS calibration is mostly complete and the instrument's performance in orbit is largely as expected before launch. The effects of ionising radiation on the detectors, and the techniques used to minimise them are outlined. The overall sensitivity figures achieved in practice are summarised. The standard processing of LWS data is described.

Astronomy and Astrophysics, 1998

We report mid-IR wavelength observations toward the low mass star forming region IRAS 16293-2422 ... more We report mid-IR wavelength observations toward the low mass star forming region IRAS 16293-2422 between 45μm - 197μm with the Long Wavelength Spectrometer (LWS) on board ISO, and of the CI(609μm) line observed with the JCMT. A map of the CII(157μm) line shows that the region is relatively uncontaminated by Photo-Dissociation Region-like emission; there is only weak diffuse CII emission, which results from the illumination of the cloud by a faint UV field (G o ~ 6). The observed CI(609μm) line intensity and narrow profile is consistent with this interpretation. On-source, the LWS detected the OI(63μm) and several molecular lines. In this work we report and discuss in detail the lines which dominate the 43μm - 197μm spectrum, namely CO, H 2 O and OH rotational lines and the OI(63μm) fine-structure line. Combining the CO J up =14 to 25 observations with previous J up =6 measurements, we derive stringent limits on the density (~ 3 * 10 4 cm -3 ), temperature (~ 1500 K), and column dens...

In this paper, IRAS, ISO, and molecular line observations of the M8 and M8E sources in the Lagoon... more In this paper, IRAS, ISO, and molecular line observations of the M8 and M8E sources in the Lagoon Nebula are reported.

Astronomy and Astrophysics, 1996

We present a high signal-to-noise ISO Long Wavelength Spectrometer (LWS) grating spectrum of the ... more We present a high signal-to-noise ISO Long Wavelength Spectrometer (LWS) grating spectrum of the planetary nebula NGC 7027 from 43-194μm. In total 40 emission lines have been detected, with 30 identified. From the ionized region, we observe fine-structure lines from [N II], [N III] and [O III]. The [O I] and [C II] fine-structure lines from the photodissociation region are the strongest features observed in this spectral region. Amongst the molecular lines, 11 pure rotation CO lines from J=14-13 up to J=24-23 have been detected. The most striking result, however, is the detection in this carbon-rich nebula of the o-H_2_O 179.53μm and the OH 119.3μm fundamental lines. Astrophysical implications are briefly discussed.

The Infrared Space Observatory (ISO) is an ESA cornerstone mission for infrared astronomy. Schedu... more The Infrared Space Observatory (ISO) is an ESA cornerstone mission for infrared astronomy. Schedules for launch in 1993, its four scientific instruments will provide unprecedented sensitivity and spectral resolution at wavelengths which are inaccessible using ground-based techniques. One of these, the Long Wavelength Spectrometer (LWS), will operate in the 45 to 180 micron region (Emery et. al., 1985) and features two Fabry-Perot interferometers mounted on an interchange mechanism. The entire payload module of the spacecraft, comprising the 60 cm telescope and the four focal plane instruments, is maintained at 2 to 4 K by an onboard supply of liquid helium. The mechanical design and testing of the cryogenic interferometer and interchange mechanisms are described.

We present an ISO Long Wavelength Spectrometer (LWS) grating spectrum of the oxygen-rich AGB star... more We present an ISO Long Wavelength Spectrometer (LWS) grating spectrum of the oxygen-rich AGB star W Hya from 43-197μm. The spectrum is dominated by a forest of water vapour emission lines, confirming that H_2_O molecules are the dominant coolants of the winds of these stars. We have constructed an outflow model for the H_2_O spectrum of W Hya, which successfully matches the fluxes of most of the observed H_2_O lines, using an adopted wind temperature profile. These fits are sensitive to the mass loss rate, to the H_2_O abundance and to the inner radius of the H_2_O emitting region. The best fit parameters correspond to a mass loss rate of 6x10^-7^Msun_/yr, inner and outer radii for the emitting region of 1.5x10^14^ and 1x10^16^cm, and a H_2_O/H_2_ abundance of 8x10^-4^ for r <=4.5x10^14^cm and 3x10^-4^ at large radii. A decrease of the H_2_O/H_2_ abundance in the outer envelope is consistent with the predictions of photochemical models. The availability for the first time of obse...

Annales Geophysicae, 2003

Monthly Notices of the Royal Astronomical Society, 1984

Monthly Notices of the Royal Astronomical Society, 1983

Monthly Notices of the Royal Astronomical Society, 1982

Monthly Notices of the Royal Astronomical Society, 1984

Astronomy and Astrophysics, 1998

Astronomy and Astrophysics, 1996