To open a page in a new browser window in an ASP.NET MVC application, you can use the target attribute of the anchor (<a>) tag. Here's an example:

<a href="@Url.Action("ActionName", "ControllerName")" target="_blank">Open Page</a> 

In this example, ActionName and ControllerName should be replaced with the appropriate values for the action method and controller you want to open in the new window.

The target="_blank" attribute tells the browser to open the link in a new window or tab, depending on the user's browser settings.

Alternatively, if you want to open a new window or tab using JavaScript, you can use the window.open() method. Here's an example:

<a href="#" onclick="window.open('@Url.Action("ActionName", "ControllerName")'); return false;">Open Page</a> 

In this example, when the link is clicked, the window.open() method is called with the URL generated using @Url.Action(). The return false; statement prevents the default action of the link, which is to navigate to the URL specified in the href attribute. Instead, the window.open() method is invoked, opening the URL in a new window or tab.

Remember to replace ActionName and ControllerName with the appropriate values for your application.