English Posts

Abstract : In this Post we want to show that a simple LED can be used as a single photon detector. The SPAD device (single photon avalanche detector) is a photodiode-like device that can react to a single photon producing a measurable current pulse. We show that a normal red LED …

Action Potential In physiology, an action potential occurs when the membrane potential of a specific cell location rapidly rises and falls : this depolarization then causes adjacent locations to similarly depolarize. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, endocrine cells, glomus cells, and in some plant cells. (from Wikipedia) Although plants don’t have …

There is no shortage of photomultipliers in the PhysicsOpenLab laboratory ! For this reason, we decided to use one of these instruments to measure physical phenomena characterized by low intensity light emission such as phosphorescence and bioluminescence. We have already made measurements of this type, but with different instruments, based …

Introduction In our experimental physics website, cosmic rays are an “unmissable” appointment : this physical phenomenon always offers new possibilities for experimentation and always gives many satisfactions. Over time we have used different experimental detection techniques : geiger tubes, scintillation detectors coupled to both PMT and SiPM, Cherenkov detectors. We …

Abstract : in this post we want to illustrate the construction of a biosignal amplifier based on the INA128 chip which integrates an instrumentation amplifier inside. The detection of biosignals, with their low “signal to noise” ratio, presents characteristic aspects that require careful use of electronics. We based ourselves on an …

Introduction Our friend Antonio Zanardo has carried out an interesting experiment with cosmic rays : “muography”. In this post we will describe its realization. MUOGRAPHY what is it? It is a radiographic technique used to obtain images of objects, generally of large dimensions, otherwise unattainable with other procedures (X-Rays). The …

The Sense HAT Expansion Card (Reference La Scienza con il Raspberry pi – Marco Casolino) One of the most interesting features of the Raspberry – which differentiates it from a simple low-cost computer – is that it can be connected to a series of sensors and actuators via the digital ports …

Introduction Some time ago in our laboratory we built a cosmic ray detector based on plastic scintillator and PMT : Scintillation Detector for Cosmic Muons. The goal was to experiment with this type of detectors and make cosmic rays flux measurements at various altitudes : Cosmic Rays on the Dolomites. …

The latest “born” at Micod is a driver for Geiger-Muller tubes. It is a circuit (shown in the image above) which has the function of providing the high voltage (400 or 500 V) necessary to drive a Geiger tube. The driver is characterized by numerous features : Supply voltage between …

Introduction Cosmic rays have already been the subject of numerous posts. In PhysicsOpenLab we have built numerous detectors based on Geiger tubes, on PMT coupled with scintillators, on the Cerenkov effect and also on the use of solid state sensors such as SiPM. In this post we want to resume …

A strong earthquake struck, in the night of November 26th, the area of ​​northern Albania. Our seismological instrumentation (seismometer and geophones) recorded the main event and the subsequent seismic swarm with numerous replicas (some of them of high intensity). On the same day there was also a violent shock in …

Introduction To acquire and subsequently process analog data from sensors, it is necessary to use an Analog – Digital converter : an ADC card. The possible solutions are manifold. For example, it is possible to use a PSoC chip that provides ADC components, acquire the data and subsequently transmit the …

Introduction In this Post we describe our attempt to replicate the experiment on X-ray diffraction by the DNA molecule. This experimental research, conducted at the time by Rosalind Franklin, allowed us to understand the structure of the DNA molecule. Of course working with X-rays and with “crystallized” DNA molecules is …

Introduction With a triode for high currents (known as Thyratron) it is possible to reproduce, albeit in a simplified manner, the famous Franck – Hertz experiment of 1914, which provided one of the first direct tests of the quantized model of atomic energy levels. The experimental apparatus used by Franck …

Measurement of very small Currents To measure the intensity of an electric current it is necessary to insert an ammeter in series with the circuit, so that the current measured on the ammeter is identical to the current that originally flows in the circuit under examination. Ideally, the ammeter has …