scholarly journals FUSE and the Quest for High-Resolution Spectroscopy in the Far Ultraviolet

2005 ◽  
Vol 13 ◽  
pp. 793-795
Author(s):  
H. Warren Moos
Keyword(s):  
High Resolution ◽  
Spectral Region ◽  
Velocity Structure ◽  
Ionic Species ◽  
Resolving Power ◽  
High Resolution Spectroscopy ◽  
Gas Velocity ◽  
The Status ◽  
Instrumental Resolution ◽  
Far Ultraviolet

AbstractThe Far Ultraviolet Spectroscopic Explorer (FUSE) instrument covers the spectral range 912-1187 Å with a resolving power of 15,000 to 20,000. This spectral region provides unique access for the study of many atomic and ionic species found in the interstellar medium, intergalactic medium, stars, and extragalactic objects. This paper summarizes the status of the mission and then discusses the need for higher resolution spectroscopy. Although the FUSE instrumental resolution is sufficient to separate most species, it usually it is not adequate for analyzing the gas velocity structure in detail. Implications for future missions are discussed.

scholarly journals The Structure of the HH39 Region

1987 ◽  
Vol 115 ◽  
pp. 340-341
Author(s):  
J. R. Walsh
Keyword(s):  
High Resolution ◽  
Radial Velocity ◽  
Proper Motion ◽  
High Velocity ◽  
Velocity Structure ◽  
The Other ◽  
Emission Lines ◽  
High Resolution Spectroscopy ◽  
Bow Shocks ◽  
Hh Objects

HH39 is the group of Herbig-Haro (HH) objects associated with the young semi-stellar object R Monocerotis (R Mon) and the variable reflection nebula NGC 2261. An R CCD frame and a B prime focus plate of the region show a filament connecting NGC 2261 with HH39, confirming the association between R Mon and the HH objects. This filament is probably composed of emission material. The southern knot in HH39 has brightened over the last 20 years; its proper motion has been determined and is similar to that of the other knots. A total of 8 knots can be distinguished in HH39 surrounded by diffuse nebulosity. High resolution spectroscopy of the Hα and [N II] emission lines shows the spatial variation of the radial velocity structure over the largest knots (HH39 A and C). Distinct differences in excitation and velocity structure between the knots are apparent. The observations are compatible with the knots being high velocity ejecta from R Mon, decelerated by interaction with ambient material and with bow shocks on their front surfaces.

scholarly journals Insights into the Pulsational Behaviour of δ Sct Stars

1995 ◽  
Vol 155 ◽  
pp. 337-338 ◽  
Author(s):  
L. Mantegazza ◽  
E. Poretti
Keyword(s):  
High Resolution ◽  
Resolving Power ◽  
High Resolution Spectroscopy ◽  
Full Description ◽  
Linear Dispersion ◽  
Stellar Spectra ◽  
Mode Identification ◽  
Photometric Monitoring ◽  
Scuti Stars ◽  
Made In

Extensive photometric monitoring of bright δ Scuti stars, made in the last years, allowed us to get reliable frequency determinations also in very complicated cases. Table 1 gives a full description of our photometric targets. Recently, we realized that combining photometry with simultaneous high resolution spectroscopy, in order to study line profile variations, offers the possibility to perform a much more reliable mode identification. Hence, the photometric runs of FG Vir, X Cae, HD 2724 were paired with spectroscopic ones obtained at the Coudé Auxiliary Telescope (ESO, La Silla, Chile). The stellar spectra are centred at 4508 Å and they cover a range of 37.6 Å; the resolving power is about 50000-60000 and the linear dispersion is 2.4 Å/mm.

scholarly journals The Proposed Columbus Mission: High and Low Resolution Spectroscopy in the 100–2000 Å Spectral Region

1984 ◽  
Vol 86 ◽  
pp. 72-75
Author(s):  
Jeffrey L. Linsky
Keyword(s):  
High Resolution ◽  
Spectral Range ◽  
Spectral Region ◽  
Extreme Ultraviolet ◽  
High Spectral Resolution ◽  
Low Resolution ◽  
Interstellar Gas ◽  
Scientists And Engineers ◽  
Ionization Balance ◽  
Far Ultraviolet

For the past year a Joint Working Group of NASA and ESA scientists and engineers has been defining the scientific objectives and instrument parameters for a proposed satellite to obtain far and extreme ultraviolet spectra of stars, interstellar gas, solar system objects, and galaxies. The project, now called Columbus, incorporates the scientific goals of the previously proposed NASA Far Ultraviolet Spectrograph Explorer (FUSE) and ESA Magellan missions.The prime spectral range of Columbus, 900–1200 Å, cannot be observed by IUE or Space Telescope. In this spectral range Copernicus was able to observe bright stars (mv ≤ 6) with high resolution and the Hopkins Ultraviolet Telescope (HUT) will observe faint sources at low resolution, but Columbus will be the first instrument capable of high spectral resolution observations of faint sources (mv ≈ 17). High resolution spectra in the 900–1200 Å region will permit studies of the Lyman lines of atomic H and D, the molecules H2 and HD, resonance lines of C III and O VI, and other species listed in Table 1. Columbus also is being designed to observe the 1200–2000 Å spectral region at high resolution, permitting measurements of many stages of ionization for the same atom (i.e. N I, II, III, V; C II, III, IV; and S II, III, IV, VI). The broad coverage of ionization states is essential for the analysis of interstellar and stellar plasmas where the ionization balance can be quite complex.

scholarly journals Theoretical analysis of double-crystal spectrograph for high-resolution spectroscopy of laser-generated X-rays

1992 ◽  
Vol 10 (4) ◽  
pp. 841-847 ◽  
Author(s):  
O. Renner ◽  
M. Kopecký
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Resolving Power ◽  
High Resolution Spectroscopy ◽  
High Dispersion ◽  
X Rays ◽  
Plasma Spectroscopy ◽  
Single Crystal Diffraction ◽  
Double Crystal ◽  
Quantitative Characteristics

Vertical dispersion variant of the double-crystal spectrograph is analyzed and its basic quantitative characteristics (luminosity, resolving power) are computed using ray tracing code. It is shown that geometric apparatus smearing is minimized due to high dispersion and spectral resolution may considerably exceed the single-crystal diffraction limit. Performing high-resolution spectral work, the efficiency of the double-crystal apparatus exceeds that of the flat single-crystal spectrograph. The usefulness of this method in laser plasma spectroscopy is demonstrated analyzing the detection of phosphorus He-like resonance line and its satellites.

Titan's 3-micron spectral region from ISO high-resolution spectroscopy

Icarus ◽  
2006 ◽  
Vol 180 (1) ◽  
pp. 176-185 ◽  
Author(s):  
A COUSTENIS ◽  
A NEGRAO ◽  
A SALAMA ◽  
B SCHULZ ◽  
E LELLOUCH ◽  
...  
Keyword(s):  
High Resolution ◽  
Spectral Region ◽  
High Resolution Spectroscopy

scholarly journals GIARPS High-resolution Observations of T Tauri stars (GHOsT)

2020 ◽  
Vol 643 ◽  
pp. A32
Author(s):  
M. Gangi ◽  
B. Nisini ◽  
S. Antoniucci ◽  
T. Giannini ◽  
K. Biazzo ◽  
...  
Keyword(s):  
High Resolution ◽  
Complex Structure ◽  
Central Star ◽  
T Tauri Stars ◽  
Resolving Power ◽  
High Resolution Spectroscopy ◽  
Young Stellar Objects ◽  
Clear Correlation ◽  
Low Velocity ◽  
T Tauri

Context. Disk winds play a fundamental role in the evolution of protoplanetary systems. The complex structure and dynamics can be investigated through the emission of atomic and molecular lines detected in high-resolution optical/IR spectra of young stellar objects. Despite their great importance, however, studies connecting the atomic and molecular components are lacking so far. Aims. In the framework of the GIARPS High-resolution Observations of T Tauri stars (GHOsT) project, we aim to characterize the atomic and molecular winds in a sample of classical T Tauri stars (CTTs) of the Taurus-Auriga region, focusing on a statistical analysis of the kinematic properties of the [O I] 630 nm and H2 2.12 μm lines and their mutual relationship. Methods. We analyzed the flux calibrated [O I] 630 nm and H2 2.12 μm lines in a sample of 36 CTTs observed at the Telescopio Nazionale Galileo with the HARPS-N spectrograph (resolving power of R = 115 000) and with the GIANO spectrograph (R = 50 000). We decomposed the line profiles into different kinematic Gaussian components and focused on the most frequently detected component, the narrow low-velocity (vp < 20 km s−1) component (NLVC). Results. We found that the H2 line is detected in 17 sources (~50% detection rate), and [O I] is detected in all sources but one. The NLV components of the H2 and [O I] emission are kinematically linked, with a strong correlation between the peak velocities and the full widths at half maximum of the two lines. Assuming that the line width is dominated by Keplerian broadening, we found that the [O I] NVLC originates from a disk region between 0.05 and 20 au and that of H2 in a region from 2 and 20 au. We also found that H2 is never detected in sources where [O I] originates in regions below 1 au, as well as in sources of early (~F-G) spectral type with a luminosity >1 L⊙. Moreover, in seven sources, both H2 and [O I] have clear blueshifted peaks and prominent [O I] high-velocity components. These components have also been detected in sources with no relevant centroid shift. Finally, we did not find any clear correlation between vp of the H2 and [O I] NVLC and the outer disk inclination. This result is in line with previous studies. Conclusions. Our results suggest that molecular and neutral atomic emission in disk winds originate from regions that might overlap, and that the survival of molecular winds in disks strongly depends on the gas exposure to the radiation from the central star. The presence of jets does not necessarily affect the kinematics of the low-velocity winds. Our results demonstrate the potential of wide-band high-resolution spectroscopy in linking tracers of different manifestations of the same phenomenon.

scholarly journals XUV and Soft X-Ray Radiation from Laser Produced Plasmas as Laboratory Spectroscopic Sources

1984 ◽  
Vol 86 ◽  
pp. 212-212
Author(s):  
P. Gohil ◽  
M.L. Ginter ◽  
T.J. McIlrath ◽  
H. Kapoor ◽  
D. Ma ◽  
...  
Keyword(s):  
High Resolution ◽  
Laser Beam ◽  
Spectral Region ◽  
Focal Spot ◽  
Laser Energy ◽  
Diffraction Limit ◽  
High Resolution Spectroscopy ◽  
Diode Array ◽  
X Ray ◽  
Pin Photodiode

Laser produced plasmas have been shown to be excellent sources for applications in the XUV and soft X-ray spectral region. We are using a 550 mj, 25 ns (FWHM) ND:YAG laser operating at a repetition rate of 10 Hz to produce plasmas above rotatable solid targets. The focal spot of the laser beam with a 31 cm lens was measured to be 170 μm (approximately twice the diffraction limit), using a diode array having a 170 μm resolution. Broadband output in the soft X-ray region was studied using a windowless PIN photodiode with an A1203 surface covered with a polyethylene filter with transmission between 44 Å and 120 Å. Results are presented for the source’s soft X-ray intensity for several elements as a function of laser energy, focus and driving wavelength, as are preliminary results using the source for high resolution spectroscopy and for soft X-ray lithography.

scholarly journals Ultra-High Resolution Ca II Observations of the LISM

1997 ◽  
Vol 166 ◽  
pp. 37-40
Author(s):  
Barry Y. Welsh ◽  
Rosine Lallement ◽  
Ian Crawford
Keyword(s):  
High Resolution ◽  
Velocity Structure ◽  
Interstellar Cloud ◽  
Complex Velocity ◽  
Velocity Pattern ◽  
Preliminary Results ◽  
Local Interstellar Cloud ◽  
Line Absorption ◽  
The Status

AbstractWe report on the status of a long-term program of mapping the velocity structure of the local ISM using ultra-high resolution observations of Call K-line absorption towards nearby B and A-type stars. Absorption components common to the local interstellar cloud (LIC) have been detected in many (but not all) lines-of-sight. Our preliminary results indicate that the local ISM has a complex velocity pattern of inhomogeneous absorption, indicative of a shocked filamentary nature.

High Resolution Spectroscopy of Dite Tokamak in the 10Å Region

1988 ◽  
Vol 102 ◽  
pp. 91-94
Author(s):  
J. Dunn ◽  
R. Barnsley ◽  
K.D. Evans ◽  
N.J. Peacock
Keyword(s):  
Fine Structure ◽  
High Resolution ◽  
Spectral Region ◽  
Intensity Ratio ◽  
High Resolution Spectroscopy ◽  
X Ray ◽  
Experimental Values

AbstractAn account is given of the X-Ray emission from the DITE tokamak in the spectral region 4Å–10Å measured by a Johann curved crystal photographic spectrometer. This high resolution instrument has been used for detailed line identifications eg. of L-shell transitions in the Fe spectrum at wavelengths ∼8Å and of the He-like ion spectra of Al, Si and Ar. The fine structure has been resolved for H-like Mg, Al and Si. Departures from the statistical value of 0.5 forβ, the intensity ratio of the Lyman-αdoublet, have been observed. Experimental values for the fine structure separation are presented for these medium Z metals.

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