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The undergraduate science programme was launched at the Indira Gandhi National Open University (IGNOU) in 1991-92 with an enrolment of 1,210 students. The programme was well received, and enrolments increased over the years. However, the success rates have not kept pace with enrolment.In this paper, the authors report the results of an evaluation of the undergraduate physics programme at IGNOU. The evaluation, the first of its type for this programme, adapted the major tenets of the CIPP model. The findings are based on the responses from a randomly chosen sample of 509 learners across India. The methods employed for the study include records, document, and database analysis, surveys, and case studies.Although the University has enhanced access to higher science education, the attrition rate is high (73%), and the success rate is low. The authors recommend that the University review and reorient its strategies for providing good quality, learner-centred higher education in science subjects. The programme should address the concerns of the learners about the effectiveness of the student support systems, the difficulty level, and the learner-friendliness of study materials with the goal of achieving long-term sustainability while maintaining parity with the conventional system. The need for improving the presentation of the courses and simplifying the mathematical details is emphasised.

This paper studies the surface plasma wave excitation via Cerenkov and fast cyclotron interaction by a density modulated electron beam propagating through a magnetized dusty plasma cylinder. The dispersion relation of surface plasma waves has been derived and it has been shown that the phase velocity of waves increases with increase in relative density δ(= n io / n e0, where n i0 is the ion plasma density and n e0 is the electron plasma density) of negatively charged dust grains. The beam radius is taken slightly less than the radius of dusty plasma cylinder. The frequency and the growth rate of the unstable wave instability increases with increase in the value of δ and normalized frequency ω/ω pe . The growth rate of the instability increases with the beam density and scales as one-third power of the beam density in Cerenkov interaction and square root of beam density in fast cyclotron interaction. The dispersion relation of surface plasma waves has been retrieved from the derived dispersion relation by considering that the beam is absent and there are no dust grains in the plasma cylinder.

Lower hybrid wave excitation in magnetized plasma by an ion beam via Cerenkov interaction is studied. The lower hybrid modes showed maximum growth rate of the instability when phase velocity of the lower hybrid mode along the magnetic field is comparable to the electron thermal velocity. We have derived the expression for the maximum growth rate and found that the growth rate of the instability increases with beam density. Moreover, the maximum growth rate of the instability scales as the one-third power of the beam density. The real part of the frequency of the unstable wave increases as almost the square root of the beam energy.

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