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The radiative transfer equation is written in microscopic form, and from some simplifications on the ratio of occupation numbers for upper and lower level, a laser action is suggested. There is an HTML version of this paper.
It is shown that 14 lines in the absorption spectrum of PKS 0237-23 coincide with He I lines (at zero redshift). Eight of these arise from the 2-1P0 level, which is at 21.13 eV. From this it appears that the absorption is taking place in a region which is at a high temperature. Simplest solution is to assume that PKS 0237-23 is a star. Emission features are identified with He I, N II and N II (Wolf-Rayet analogy).
Analysis of the strong emission line data of 247 QSOs shows that these are consistent with the following hypotheses:(1) There is no redshift, (2) the composition of the emission region is the same as that of the Wolf-Rayet stars, and (3) there is laser action. Search is made for such wavelengths which satisfy the following criteria: (a) it occurs as a strong line in a QSO, (b) it occurs in Wolf-Rayet stars and the transition has been identified, and (c) laser action for this transition has been observed in the laboratory. This leads to the following identifications. 3748 Å, occurring in BSO 11 and RS 32, and 4349 Å, occurring in 3C 432 and PKS 1136-13, are both due to O II. 4515 Å observed in 3C 261, is due to N III, and 4652 Å, observed in PHL 1377, is probably due to C III.
Analysis of the four available sets of the absorption spectrum measurements has been carried out on the assumption of zero redshifts. It is concluded that PKS 0237-23 is a shell star and it is undergoing changes. Also it appears to be deficient in hydrogen. The following identifications are made. H (some middle members of the Balmer series blended with other lines), He I (lines in Varshni, 1973 in addition to 3472 Å, 3499, 3502, 3537, 3563, 3614, 3769, 3820, 3838, 3889, 4026, 4471, and 4922), He II (3203), O II (3727, 3760, 4349, 4417), Ne II (3664, 3694, 3710, 3727), Mg I (3838), Mg II (4481), Si I (3905), Si II (3854, 3856, 3863, 4128), Si III (3762, 4089), P IV (3348, 3364, 3718, 3729), Ca II (3934, 3968), Ti II (3349, 3685, 3759, 3761, 3900, 3913, 4012, 4395), V II (3590, 3592), Cr II (4012, 4262, 4284), Fe I (3748, 3860, 3879, 4326, 4462), Fe II (4233, 4273, 4297, 4385, 4417, 4455, 4491, 4520, 4584, 4924), Sr II (4078, 4215), and Zr II (4149 Å).
It is shown that the distribution of absorption-line redshifts for the quasar 4C 05.34 is consistent with the hypothesis that the proposed systems arise because of chance coincidences between the wavelengths of the search lines (at appropriate values of z) and the wavelengths of the observed absorption lines.
The author has recently shown that the spectra of quasi-stellar objects can be explained by the hypotheses that there is no red shift and that the strength of emission lines is due to laser action. A realistic model of the QSOs, based on these hypotheses is proposed. A QSO is a star with a rapidly expanding atmosphere, in which population inversion is occurring. This atmosphere can be approximated by a decaying plasma. Properties of such a plasma are reviewed. A given transition in an atom can undergo laser action only within narrow ranges of the electron density (ne), electron temperature (Te) and the density of the ground state atoms (n(1)). ne, Te, n(1) plot is introduced to classify the QSOs. Consequences of the proposed model are discussed. Intensity variations of the same line in different QSOs, and also in the same QSO, are shown to follow naturally from this model. Quantization in the red-shift is explained. Polarization of strong emission lines is predicted.
Analysis of the strong emission-line data of 281 QSOs shows that these are consistent with the following hypotheses : (1) There is no redshift, (2) The strength of the emission lines is due to laser action, and (3) The composition of the emission region of QSOs is approximately the same as that of normal stellar atmospheres. A search was made for common lines in QSOs and in laboratory observed laser lines in such atoms and ions, which have high abundance in stellar atmospheres. Twenty-four such wavelengths were found. A realistic model of the QSOs, based on these hypotheses is proposed. A QSO is a star with a rapidly expanding atmosphere, in which population inversion is occurring. This atmosphere can be approximated by a decaying plasma. Properties of such a plasma are reviewed. A given transition in an atom can undergo laser action only within narrow ranges of the electron density (ne), electron temperature (Te) and the density of the ground state atoms n(1). ne, Te, n(1) plot is introduced to classify the QSOs. Consequences of the proposed model are discussed, taking the group consisting of 3C 191, PHL 938, PKS 0119-04 and BO 6 as an example. Other similar groups are pointed out (e.g., RS 23, PHL 1222, and 1548+115b). Intensity variations of the same line in different QSOs, and also in the same QSO, are shown to follow naturally from this model. Quantization in the redshift distribution is explained. Absorption spectra of QSOs are also discussed.
The reality of red-shifts in the emission and absorption spectra of QSOs is questioned. Investigations in the spirit of the paper by Russel and Bowen (1929, Astrophys.J. 69, 196) are carried out to examine the question of whether the numerical coincidences found between the ratios of wavelengths of lines observed in the QSOs and those of the wavelengths of lines in the search list are significantly more than would be expected from chance coincidences. QSOs having z > = 0.2 are considered. Computer experiments to simulate the spectra of two-emission-line QSOs is described; about 85 percent of these nonsense spectra can be assigned reasonable redshifts. The redshift distribution of QSOs is calculated on the chance coincidence hypothesis and is found to be in broad accord with the observed one. Large discrepancies between the observed and calculated emission line wavelengths (on the redshift hypothesis) for a number of QSOs are pointed out. Distribution of absorption-line red-shifts of 4C 05.34 is shown to be nearly the same as that expected from the chance coincidence hypothesis and the plasma-laser star (PLS) model of Varshni ( 1974) in explaining the following points are compared: (1) Redshift-apparent magnitude diagram, (2) Coincidences in redshifts, (3) Relative intensities of lines, (4) Profile of lines, (5) Energy generation mechanism, (6) Optical Variability, (7) Lyman-alpha absorption, and (8) Radio data. It is found that the PLS model provides satisfactory answers on all scores, while the redshift hypothesis leads to enigmas, mysteries and paradoxes.
Using four well-defined rules, Bahcall and Goldshith (1971, Astrophys.J., 170, 17) (BG) have proposed eight absorption redshift systems for the QSO 4C 05.34. These systems identify 47 lines out the 93 observed. BG have also analysed 10 nonsense spectra; they find that for the 'average' nonsense spectrum, the number of acceptable redshifts is only 1.4, and the total number of line identified is only 7. It is pointed out that BG have missed out a vital point, namely, the density distribution of lines, in generating their nonsense spectra. Following the basic ideas of Russel and Bowen (1929, Astrophys.J. 69, 196), ten nonsense spectra are generated which are similar to the real spectrum in all its statistical characteristic features. Such spectra are named ghost spectra. These are analysed using the rules of BG, and the results are as follow. For the 'average' ghost spectrum, the number of acceptable redshifts is 8.4 ± 0.92, and the total number of lines identified is 35.5 ± 5.39. The problem of multiple identifications for an observed line is discussed, and the results obtained from the chance-coincidence hypothesis are compared to the actual ones. It is concluded that the number and properties of the absorption redshift systems proposed by BG for 4C 05.34 are insignificantly different from those that would be expected from chance coincidences. The foregoing results further strengthen the suggestion that there is no redshift in QSOs (Varshni, 1974)
In the plasma-laser star model for QSOs (Varshni, 1973a, 1973b, 1974a, 1974b) the line 4686 Å very likely arises due to laser action in the n=4 to 3 transition in He II. Extensive calculations of population densities in hydrogenic ion plasmas are carried out for a grid of ne (electron density), Te (electron temperature) and n(1) (density of the groundstate atoms) values on the basis of the collisional-radiative model (Bates, Kingston and McWhirter: 1962 Proc.Roy.Soc. A267, 297, Drawin: 1969 Zs.Physik, 225, 470). The region in which the population inversion is most intense for 4686 is identified and the bearing of the result on the atmospheres of the quasars 3C48, 4C09.31, PKS2059+034 and 4C37.43 and also of Of stars is discussed.
The following question is raised: Are the numerical coincidences found between the ratios of wavelengths observed in QSOs and those in the wavelengths given in standard search list of lines, significantly more than what would be expected from chance coincidences ? QSOs having z >= 0.2 are considered. Rules for redshift fittings are described with reference to the 20 prominent lines in the search list. Computer experiments to simulate the spectra of two-emission-line QSOs are described. It is found that about 80 percent of the nonsense spectra can be assigned reasonable redshifts. Next, the redshift distribution of QSOs is calculated on the chance coincidence hypothesis and is found to be in broad accord with the observed one. It is concluded that the answer to the question raised in the opening sentence is in the negative. The plasma-laser star model (see Varshni and Lam, 1974) is discussed.
Ten ghost spectra which simulate the absorption-line spectrum of the QSO 4C 05.34 (0805+046) are generated on a computer and analyzed according to the rules of Bahcall and Goldsmith. The results conclusively show that the number and properties of the absorption redshift systems proposed by Bahcall and Goldsmith are insignificantly different from those that would be expected from chance coincidences.
It is shown that the emission lines observed in quasars can be satisfactorily explained as being due to laser action in certain atomic species in the expanding envelope of a star. There is not need to assume a redshift
(The term 'galactic' here includes the galactic halo) Available observational material on 3C 273 is critically examined with reference to the redshift hypothesis and the plasma laser star (PLS) model of Varshni ( 1974a, 1974b, 1974c) (a) Emission lines. Large uncertainties in the reported wavelengths (Schmidt 1963, Oke 1963, Greenstein and Schmidt 1964, Andrillat and Andrillat 1964, Oke 1965, Divan 1965, Wampler and Oke 1967, Wampler 1969) are pointed out. In the redshift interpretation, [O III] 5007 Å is present, but 4959 Å is not, which is clearly unsatisfactory. In the PLS model, the following identifications are proposed: 3239 Å is due to O III, 7598 Å is due to C III (Edlen 1956). Astronomers are urged to obtain more accurate wavelengths of the emission lines. It would also be of interest to obtain the spectrum of the jets (3C 273A) alone. (b) Interstellar K and H absorption lines have been observed in the spectrum of 3C 273 (Williams 1965). High resolution studies of the profiles and intensities of these lines in 3C 273 and in other QSOs are expected to throw light on the distances of QSOs. (c) Divan (1965) has shown that the absolute energy distribution in the continuum is like that of a black body with a color temperature of 11,300 K. (d) Latest radio observations (Kellermann 1974) on the angular size find a natural explanation if 3C 273 is a galactic object. (e) Optical Variability. (f) Similarities between the spectra of 3C 273, NAB 0205+02 and 4C 39.25 are pointed out. It is concluded that the available evidence favors the view that 3C 273 is a galactic star.
Menzel (1970) has given a clear discussion of the possibility of laser action in non-LTE atmospheres. Gudzenko and Shelepin (1963) and Gudzenko et al. (1966) have proposed that if the is sufficiently rapid cooling of the free electrons when a plasma expands, there can be a population inversion in the lower levels of an atom. It is shown that in high-temperature stars in which high speed mass loss is occurring, the rapidly recombining plasma in the stellar envelope can act as an amplifying medium. Model calculations for laser action in He II 4686 Å, using the collisional-radiative model (Bates et al. 1962), are presented. The results are presented in terms of the population inversion measure P=N2/g2 - N1/g1. P=N2/g2 - N1/g1. (N is atomic population, and g, statistical weight). P is shown as a function of the electron density and electron temperature in the figure. The numbers by the side of contours represent P values in per cubic cm. The bearing of the results on the spectra of Wolf-Rayet stars those of planetary nuclei is discussed.
The envelope function in the largest angular size (LAS) - redshift (z) diagram for 164 quasars for which data are available (Miley, 1971,M.N.R.A.S. 52, 477; Wardle and Miley, 1974, Astron.Astrophys. 30, 305) is discussed. A histogram showing a distribution of LAS of quasars is plotted. making use of the sampling theory, quasars are distributed in compartments having redshift widths of 0.2 and LAS widths of 20 arcsec. The resulting distribution is quite similar to that of figure 3 of Wardle and Miley. It is concluded that the observed distribution of points in the LAS-z plot is just a reflection of the redshift distribution of quasars, and its envelope has no intrinsic physical significance. The LAS and z values of quasars were randomly paired on a computer. The resulting LAS-z plots are quite similar to figure 3 of Wardle and Miley. These results are consistent with our contention that there are no redshifts in quasar spectra. Varshni ( 1973, 1973, 1974a, 1974b)
The envelope function in the largest angular size-redshift diagram for quasars is shown to be a consequence of the distribution of their redshifts and to have no intrinsic physical significance. There is an HTML version of this paper.
It is shown that the cosmological interpretation of the red shift in the spectra of quasars leads to yet another paradoxical result: namely, that the Earth is the center of the Universe. Consequences of this result are examined. There is an HTML version of this paper.
It is pointed out that Stephenson (1977) has used incorrect dz, and has also made an arithmetical error, which invalidates his claims. Tests for randomness of quasar red-shift clusters, using correct dz, have been carried out and it is shown that at least for clusters having three red shifts or more, the distribution is highly non-random. The model of the Universe proposed by Stephenson does not in any way explain these red-shift clusters; it merely substitutes one paradox by another. There is an HTML version of this paper.
It is shown that in high-temperature stars in which high speed mass loss is occurring, the rapidly recombining plasma in the stellar envelope can act as an amplifying medium. Model calculations for laser action in He II 4686 Å, using the collisional-radiative model, are presented. Menzel's hypothesis of laser action in distended stellar atmospheres is shown to be fully substantiated. The relevance of these results in resolving the problem of intensity anomalies in the spectra of Wolf-Rayet stars is pointed out
The plasma-laser star model for quasars, which is based on the hypothesis that there is no red shift in the spectra of quasars and that the strength of the emission lines is due to laser action, is further developed. Continuity is shown to exist between the spectra of O VI sequence planetary nuclei, Sanduleak stars, and 10 quasars. The O VI 3811 Å, 3834 Å and He II 4686 Å emission lines in the spectra of these 10 quasars are identified. Candidate identifications for other quasar lines are also suggested. Making use of the similarity between the spectra of O VI sequence planetary and those of the 10 quasars, absolute magnitudes, temperatures, and masses of these quasars are estimated. The distribution of quasars in galactic coordinates is also discussed. Three predictions are made. There is an HTML version of this paper.
The Inglis-Teller relation, generalized for a hydrogen-like or alkali-like ion with an arbitrary core charge, is used to estimate the electron density in the emission-line region of Wolf-Rayet stars. It is found that the electron density in the region which gives rise to He II emission lines is about 4 X 10^14 cm^-3.
The plasma laser star (PLS) model for quasars proposed by the author, is applied to explain the absorption spectra of quasars. The following topics are briefly reviewed (a) Shell stars, especially gamma Cas. The role of the metastable states. He I 3889 Å. (b) High Rydberg states. (c) Multiply-excited states of atoms (and ions) which lie above the first ionization potential, especially the Wu states (metastable states which cannot autoionize by Coulomb interactions or decay radiatively. Prototype 1s2s2p P quartet state of the Li I sequence). (d) Dielectronic recombination. The expected shell spectrum of a quasar on the basis of the PLS model is compared with the observational data. The absorption lines arising from ordinary excited levels will be very weak as these levels will be strongly underpopulated (bn < < 1). The populations of metastable levels below the first ionization potential and those of the Wu levels will be enhanced due to the dilution of stellar radiation. Consequently, lines arising from these levels are expected to be prominently. Those arising from the Wu states will be difficult to identify as very few of these have been observed in the laboratory. The difficulties in the identification of observed lines due to the blending of lines due to the rather large uncertainties in the measured wavelengths are discussed. The presence of He I 3889 Å in the spectra of PHL 957, 1331+170, 4C 25.05, PHL 5200, PKS 0237-23 and 1158+122 is noted. A very reasonable explanation of the absorption 'hole' at 4020 Å in the spectrum of PHL 957 is that it is due to a transition from a Wu level to an autoionizing level. Also, there is no need of assuming redshifts in the spectra of two BL Lac objects, namely 0725+178 and AO 0235+164.
One is led to attribute to quasars very many mysterious properties if one assumes the redshift hypothesis to be correct. A patient analysis of the data on quasars over the years led the author to the conclusion that the real source of the trouble is in the assumption that the spectra of quasars have redshifts. In 1973 the author proposed a radically different explanation of the spectra of quasars. In this paper we give the salient features of this theory and compare it to the cosmological redshift hypothesis. For the sake of clarity we shall confine ourselves to quasars in this paper. There is an HTML version of this paper.
A study of some statistical properties of the transverse motion of the central stars of 62 planetary nebula is presented. It is found that, at low values, the observed proper motion is independent of distance.
Walsh et al. (1979, Nature, 279, 381) have discovered a double quasar 0957+561, which is of considerable interest. The red magnitudes of the two components, A and B, are identical, being 17, while the blue magnitudes are slightly different. The two components are separated by 5.7 arcsec. The emission spectra of both are extremely similar. Radio observations of 0957+561 have been carried out by Roberts et al. (1979, Science, 205, 894; Bull.Am.Astron.Soc., 11, 620), and by Pooley et al. (1979, Nature, 280, 461). We have proposed a theory of quasars (Varshni, 1973, 1974a, 1974b, 1975, 1977, 1979 and 1985) based on sound physical principles and here we shall estimate the distance of 0957+561 on its basis. Both the components belong to the same group, namely 20, in our spectral classification of quasars. The most natural explanation of the existing observations is that 0957+561 is a binary star embedded in a nebulosity which gives rise to the common absorption lines. We shall draw upon the data for known stars for estimating the distance of 0957+561. From Eggen's compilation (1956, Astron.J. 61, 405) we have selected such binaries which satisfy the following conditions: 1. Spectral types of both components are separately known. 2.Differences between the magnitudes is less than two. Twenty-nine binaries satisfying these conditions were found. In most cases, the spectral types of the two components are quite close; indeed, for seven of them, the spectral types are identical. The similarity with the case 0957+561 is obvious. From a histogram of the number of binaries versus rho/pi (rho=angular separation, pi=trigonometric parallax), it is seen that a great majority (75 percent) of the systems under consideration have rho/pi less than 500 arcsec pc. If we assume that 0957+561 falls in this class, its distance is estimated to be less than 100 pc. The largest value of rho/pi in our list is about 1500 arcsec pc; corresponding to this value, the distance estimate for 0957+561 is 300 pc.
The population densities of the discrete levels of the lithium-like ions C IV, N V, and O VI in optically thin plasmas cooled by adiabatic expansion have been calculated with the Collisional-Radiative (CR) plasma model, suitably modified to account for the small energy separation of the ground and the first excited states of these ions. The following elementary processes have been included in the CR model: electron impact ionization, excitation, and de-excitation, three-body and radiative recombination, and spontaneous transitions. The data and calculations available on these processes have been analysed and extended by various methods. The resulting rate coefficients are compared with the corresponding hydrogenic values, and a discussion of their accuracy is given. Population inversions have been found to occur in many of the transitions of these ions. We have concentrated our attention to such transitions of the ion C IV between levels with n < =6 which give rise to emission lines in the visible region of the spectrum. The gain of the inversely populated transitions is presented in the form of ne-Te diagrams. The C IV 4646, 4658 Å lines arising from the 6f-5d and 6g-5f transitions respectively, are found to be strongly inverted and should be excellent candidates for producing laser action in laboratory plasmas cooled by adiabatic expansion techniques. In addition, the behavior of the line C IV 4650 Å observed in the WC category of the Wolf-Rayet stars is found to be in agreement with that expected from the model calculations. The present investigation thus provides an understanding of the unusual strength of the C IV 4650 Å emission in Wolf-Rayet stars, and provides a strong basis for believing that laser action is responsible for it.
It is shown that the number of redshift systems based on C IV doublets, proposed by Boronson et al. (1978) in the absorption spectrum of the quasar PKS 0237-23, is insignificantly different from that that would be expected from chance coincidences. Consequently, these systems and their z-values appear to be devoid of any physical significance. There is an HTML version of this paper.
The author's theory that quasars are stars raises the question of their proper motions. From the evidence presented in a previous paper, it is hypothesized that planetary nuclei and quasars are related objects and that their distributions in the galaxy are not very different. Proper motions of 30 quasars, calculated from existing measurements, are discussed. It is shown that three of these, namely PHL 1033, LB 8956 and LB 8991, have proper motions comparable to the largest motion known amongst the planetary nuclei. From this it is estimated that these three quasars lie within a few hundred parsecs from the sun. The evidence presented in a previous paper and the present one clearly support our theory that quasars are stars. The possibility of using the interstellar K and H lines as distance indicators of quasars is discussed and the available evidence summarized. The desirability of determining more accurate values of the proper motions of quasars is emphasized. There is an HTML version of this paper.
It is shown that the number of redshifted CO absorption-line systems that are found in the spectrum of the quasar PKS 0237-233, using the rules of Varshalovich and Levshakov, is insignificantly different from that which would be expected from chance coincidences. Consequently, the CO systems proposed by Varshalovich and Levshakov have no physical reality'
Dr. Varshni of the University of Ottawa spoke to the center on Wednesday, March 21, about the subject of quasars. Dr.Varshni pointed to significant evidence which indicates that quasars are, in fact, nearby objects, quite faint, within our galaxy. They are too faint to be seen in external galaxies. The main phenomena which accounts for the spectral lines of quasars is a laser effect, which is producing radiation as a result of a rapidly-cooling plasma, such such as would be produced by a star during the production, say, of a planetary nebula. Depending on the constituent elements of the star, the temperature, the temperature of the plasma, the rate of expansion, and other effects, a large number of spectral lines may be produced. It is thus very easy to confuse these lines with red-shifted lines of other elements, such as the hydrogen line. Dr. Varshni showed examples of several quasar spectra, which actually showed several coincident lines, which were not red-shifted, but several coincident lines, which were not red-shifted, but corresponded to lines which may also be found in planetary nebulae. The broadening of spectral lines of quasars is due to the rapid expansion of the plasma which produces the laser effect, this expansion taking place in all directions. Also shown were measurements of the proper motions of quasars, which is much harder to explain if they were distant objects. It is suggested that the new space telescope be used to study the proper motions of quasars more closely, and this would resolve the issue. It was also noted that more search should be made for quasars along the galactic axis. If quasars really are distant, they should not be visible here, but this area has not been studied for quasars.
Within the framework of the plasma-laser star model of quasars (Varshni, 1975, 1977, 1979) it is proposed that 0805+046 is a helium-rich shell star. (a) The strong emission line at 4712 Å is identified with He I 4713 Å. (b) The discontinuity in the continuous energy distribution at 3420 Å is identified with the helium discontinuity at 3422 Å . (c) In the absorption-line spectrum (Jian-sheng et al.: 1981,MNRAS., 196, 715), many lines have been identified. Some of the identifications are given below:
Libby et al. (1984, AJ., 89, 311. online) have studied the absorption-line data for 13 QSOs in the rest frames of the QSOs. It is shown that the number of groups in which 5 lines or more lie within a wavelength interval of 1 Å found by these authors is insignificantly different from that that would be expected from chance coincidences. Consequently, there is no evidence that the rest-frame wavelengths at which these groups occur have any physical significance'. There is an HTML version of this paper.
Within the framework of the plasma-laser star model of quasars it is proposed that the quasar 0805+046 is a helium-rich shell star. (a) The strong emission line at 4712 Å is identified with He I 4713 Å. (b) The discontinuity in the continuum energy distribution at 3420 Å is identified with the helium discontinuity at 3422 Å. (c) In the absorption-line spectrum many lines have been identified. It is shown that the proposed model provides a consistent and satisfactory interpretation of the observed spectra. There is an HTML version of this paper.
Model calculations for laser action in He I are carried out, when helium plasma is rapidly cooled by expansion. Results are presented for four transitions, two of which, 3S to 2P singlet (7281 Å) and 3D to 2P singlet (6678 Å), show strong population inversion. Available observational evidence for possible laser action in these two lines in Wolf-Rayet and emission-line stars is summarized and discussed.'
A similar model for laser action in C III is carried out. A total of 59 states of C III are considered in the Collisional-Radiative model. All the elementary processes mentioned above are included, in addition, we include the dielectronic recombination. Accurate oscillator strengths for the allowed electric dipole transitions between 40 lowest terms in C III required in the calculations have been calculated. The method of calculation and the results of these oscillator strengths are given and compared with previous results and experimental values, where available. Also, a modified ionization equilibrium model for carbon, applicable to high and low electron densities, is used to calculate the relative concentrations of various ions. Appreciable population inversion is found to occur only in two lines 2s3p ^3P^0 to 2s3s 3^S (4650) and 2p3p ^3S to 2p3s ^3P^0 (5263) in the visible region. The results are presented in the form of ne-Te diagrams. The relevance of these results in resolving the problem of intensity anomalies in the spectra of Wolf-Rayet stars is pointed out.
Extending the model calculation for He I, the sudden cooling assumption is removed and the plasma is allowed to expand in finite time. The initial population densities of excited states of He I are calculated using steady-state assumption. The differential equations for the population relaxation, electron density, ion densities and electron temperature are solved jointly using Runge-Kutta-Gill method. The variations of population densities with time are presented and discussed. The effect of initial conditions of the helium plasma on the population inversion is studied. A similar model is applied to carbon plasmas. The evolution of the densities of the levels of C III are investigated in detail. The calculation is carried out for three sets of initial conditions to study the dependence of the population inversion in the C III ion on the initial plasma parameters.
Results of a theoretical model are presented, which describes a stationary He I plasma brought into contact with cool and dense hydrogen gas. The model includes elastic collision interaction and the detailed kinetic excited levels of helium and hydrogen atoms. Atom-atom collision processes are included. The quasi-steady state approximation is used only for levels i lying above a certain level i* which is greater of equal to 11 in He I and 5 in H I. Effective electron cooling is found to occur in a short time. It is found that the population inversions which occur between the levels of hydrogen atom are realized only in the quasi-steady state following the transient phase, while those in helium are realized in the transient phase. The calculations have shown that the magnitude of the population inversion which occurs between the levels of helium is much greater than that obtained previously by expansion.
Recently Warren et al. (1987, Nature, 330, 453) Have found a quasar, Q0051-279, with two broad emission lines at 6740 Å. The spectrum was observed in the interval 5400-9500 Å. Assuming the redshift hypothesis, these authors have identified these lines with N V 1240 Å and C IV 1549 Å resulting in a 'redshift' of 4.43. Ly-alpha 1216 Å appears to be absent. If these identifications are correct, they clearly throw in doubt previous 'redshifts' which are based primarily on Ly-alpha. We have proposed a theory of quasars (Varshni 1973, 1974a, 1974b, 1975, 1977, 1979, 1985) according to which there are no redshifts in quasars, the strength of the lines being due to laser action. In the framework of this theory, we identify the two lines as C III 6730, 6744 Å and C II 8413 Å . We expect that in the visible region C III 4650 Å should show up.
'The emission and absorption lines (3716-4290 Å) in the spectrum of the quasar 0237-233 are identified within the framework of the PLS model. The available evidence indicates that it is a helium star. Similarities between the spectral properties of 0237-233 and the star Upsilon Sagittarii are pointed out. Predictions are made for the absorption-line spectrum which falls outside 3716-4290 Å and also for an expected discontinuity at 2600 Å. There is an HTML version of this paper.
In recent years a number of observers ( Hutching et al. 1984, Astrophys.J.Suppl. 55, 319; Wyckoff et al. 1981, Astrophys.J. 247, 750; Gehren et al. 1984, Astrophys.J. 278, 11; Malkan et al. 1984 Astrophys.J. 280, 66; Malkan 1984, Astrophys.J. 287, 555) have carried out high-sensitivity imaging studies of quasars. Most of the objects selected were such that their apparent 'redshifts' were less than 0.7. In most of these cases a nebulosity has been found around the quasar. Assuming the cosmological hypothesis, these investigators have interpreted the nebulosity as starlight from the underlying galaxy in which the quasar nucleus resides. On the other hand, the author has proposed a theory of quasars according to which the quasars are stars which are undergoing high-speed mass loss and have no redshifts. (Varshni, 1974a, 1974b, 1975, 1977, 1985). According to our theory we interpret the nebulosity as an envelope of ionized and neutral gases which have been ejected from the quasar. Some dust may also be present. We further predict that similar nebulosity should occur around some of the Wolf-Rayet stars, planetary nuclei (which have WR type of spectra) and Be stars. We request that observations be carried out to test this prediction. The detection of nebulosity depends on the plate scale, limiting magnitude, and quality of the observations. Clearly these should be similar to those in the quasar studies. A good sample size would be desirable. The stars should not be in a crowded or obscured field.
Over the course of years, we have examined, scrutinized and analyzed the available data on the redshifts of many galaxies, especially the spectral data. We find that there is no need of assuming any redshifts in galaxies also, as was the case for quasars (Varshni 1973, 1974a, 1974b, 1975, 1979, 1988) and radio galaxies (Varshni, 1979). Small redshifts ( z < 0.003 ), like those in galactic stars, are, of course, possible. There are, of course genuine external galaxies (e.g., Andromeda, M33, etc .) but it appears that many of the objects labelled as galaxies are in reality nebulosities in our own galaxy. As an example we consider the case of 1305+2952 G8. A strong emission line at 7230 Å has been reported in this object and this line has been interpreted as [O II] 3727 Å at a 'redshift' of 0.943. Actually the line is readily identified to be C II 7231, 7236 Å (mult.3) which is undergoing laser action. Thus the object in question is a galactic object. Our conclusion of 'no redshifts' readily explains the following: (a) The large scatter of points for 'galaxies' on the (m, z) diagram. (Lang et al.: 1975, Ap.J., 202, 583) (b) Discordant 'redshifts' and other related things (Arp, 1987, Quasars, Redshifts and Controversies). It also eliminates the need of assuming a hypothetical 'missing mass'. There is a great need of better spectral data for many galaxies.
The plasma-laser star model for quasars has been used to identify the emission and absorption lines as well as the continuum discontinuities in the spectrum of the quasar 0420-388. The He I 3680 Å discontinuity is identified for the first time in an astronomical spectra. Two predictions are made. There is an HTML version of this paper.
A theoretical investigation of population inversion in C IV recombining plasmas cooled by adiabatic expansion has been carried out. The non-equilibrium plasma is simulated on computer using the Collisional-Radiative model which requires rate coefficients for basic physical plasma processes. We show how gain per unit length is computed and why large gains occur only in limited regions of parameter space (ne, Te) we then compare these results with astronomical evidence. We also show how the rate coefficients and ionization equilibrium are computed.
There is an electronic version of this paper in TEX and in PostScript format.
J. Talbot, Y. P. Varshni (Univ. of Ottawa)
One of us has proposed a theory of quasars based on sound physical principles which does not require the assumption of redshifts (Varshni, 1975, ApSS 37, L1; 1977, ApSS 46,443; 1979 Phys.Canada 35,11). According to this theory quasars are stars, the strength of the emission lines arises due to laser action. A search of Luyten's measurements (Luyten, 1969, A Search for Faint Blue Stars, Paper 50) has shown that the quasar Ton 202 (apparent z=0.366) has a substantial proper motion. From the data given by Luyten, the absolute proper motion for Ton 202 turns out to be 52.6 ms/year with a mean error of 16 ms/year. If we calculate the transverse velocity corresponding to the smallest value of the proper motion within the uncertainty range, assuming H = 50 km/sec per Mpc and q0= 0, it turns out to be 1100c. The evidence clearly indicates that Ton 202 is a star. More accurate measurements of the proper motion of Ton 202 are highly desirable. We identify the observed emission lines (wavelengths in Å): 1640 (He II 1640), 2110 (Ca II 2103,2113), 2600 (O III 2598, 2605 and C III 2610,2614,2617), 3810 (O VI 3811,3834). We note here that while most members of the same spectral class (e.g., PKS 2059+034, 4C 27.38, 4C 09.31, 3C 48, 4C 37.43 etc) show the He II 4686 emission line, Ton 202 does not. This further supports the interpretation that the strength of the emission lines is due to laser action.
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